Police were called at approximately 14:40hrs on Wednesday, 22 March to reports of an incident in Westminster Bridge, SW1. It is being treated as a firearms incident.
Officers - including firearms officers - remain on the scene and we are treating this as a terrorist incident until we know otherwise.
Investigators have now made a total of eight arrests as part of the ongoing Counter Terrorism operation.
We thank the public for their assistance.
Police are appealing for any members of the public who may have images or footage of the incident to send them to this address:
Police are asking people to avoid the following areas: Parliament Square; Whitehall; Westminster Bridge; Lambeth Bridge; Victoria Street up to the junction with Broadway and the Victoria Embankment up to Embankment tube.
This is to allow the emergency services to deal with the ongoing incident.
In a statement given outside New Scotland Yard on Friday, 24 March, Acting Deputy Commissioner, Mark Rowley, said:
"Good morning, I am here to update you on the following areas:
- update you on the breadth and speed of our investigation;
- I want to ask for the public's help; and
- provide further details on the police service response.
"First I want to update you regarding those who were injured.
"Sadly last night another man died in hospital as a result of the injuries he sustained during the attack.
"Whilst we await formal identification, we believe that he is Leslie Rhodes, aged 75, from Streatham in south London.
"My thoughts are with his family at this difficult time.
"Furthermore, two people remain in hospital in what is described as a critical condition, and one person is considered to have life threatening injuries.
"Two of our officers who were injured on Westminster Bridge in the attack also remain in hospital and also have sustained significant injuries.
"At least 50 people were injured with 31 requiring hospital treatment as the attack unfolded and those affected include a real cross section of ages and from at least 12 nationalities.
"It is a poignant reminder that the impact of this attack on the Capital will reach around the world.
"So moving onto our investigation:
"The Counter Terrorism Command investigation - Operation Classific - continues, involving hundreds of officers from across the counter terrorism network.
"This is a very large, fast-paced investigation I want to give you as much information as possible and I do want to make a critical appeal to the public
"Yesterday we named the dead terrorist as Khalid Masood - we stated he had a number of aliases - we now know his birth name was Adrian Russell Ajao.
"I would like to put on record my gratitude to the journalists who having identified the dead terrorist soon after the attack have delayed publishing his details at my request to give us space to move on the necessary warrants, searches and arrests.
"As I have said our investigation focuses on understanding his motivation, preparation and his associates.
"Whilst there is no evidence of further threats you will understand our determination to find out if he either:
- Acted totally alone inspired by terrorist propaganda;
- Or, if others have encouraged, supported or directed him;
"To that end in our continuing investigation and ongoing covert activity we have made two further significant arrests overnight - one in the West Midlands and one in North West.
"Nine people remain in our custody and one woman has been released on bail. We have searches at five addresses ongoing - 16 searches have concluded. So far we have seized 2,700 items from our searches including massive of amounts of computer data.
"We have had contact with approximately 3,500 witnesses - including 1,000 from people on Westminster Bridge and around 2,500 who were within the Parliamentary Estate, and we have received hundreds of uploads to our online platform.
"Given that this attack was in the heart of the Capital we are also dealing with statements from people with range of nationalities.
"At this point I want to appeal specifically to the public.
"We remain keen to hear from anyone who knew Khalid Masood well; understands who his associates were; and can provide with information about places he has recently visited.
"There might well be people out there who did have concerns about Masood but weren't sure or didn't feel comfortable for whatever reason in passing information to us.
"I urge anyone with such information to contact us the Anti-Terrorist hotline which is 0800 789 321.
"In terms of protective security:
"I understand why a tragic event such as this generates questions about security at Parliament.
"Our current arrangements have been developed with Parliament over many years and are designed to provide access to the seat of our Government balanced carefully with security that is proportionate but not overly intrusive.
"Of course after an incident like this as would be expected my team will work with Parliamentary authorities to assess whether a different tone or balance is necessary.
"More widely - the police service will sustain an enhanced armed and unarmed presence over the next few days.
"London, and the UK, are open for business, and we are out there in greater numbers to make sure that the public see a highly visible presence to help reassure them as they go about their daily lives.
"In London the number of armed officers remains at near double strength, while in other parts of the UK there are up to a third more armed officers on duty.
"Finally, last night a true cross section of people came together to stand together to remember - but also to send a message.
"A strong message - to those inspired by hate and extremism of all persuasions that we will not give in to those who seek to breed discord and fear.
"This is as true now as it has ever been. Our Acting Commissioner, Craig Mackey, told thousands who gathered in central London last night terrorist have tried to tear this city apart before and they have never succeeded.
"The very fact London has gone back to work and so many were happy to gather in central London last night shows they have failed again.
"We would like to thank our officers and staff who continue to work around the clock - both investigating this atrocity and continuing to keep our city safe. From the staff picking responding to calls in our control centres, staff and officers still guarding our iconic buildings, the officers patrolling streets in every borough and specialist teams that are not so visible.
"We are grateful for the continued support of the public and the strong calm response that has been shown, and I know that we will continue to stand together."
At 07:45hrs on Thursday, 23 March, Mark Rowley, the national lead for Counter Terrorism Policing and the Acting Deputy Commissioner, said:
“Good morning - I am here to update you on our ongoing counter terrorism operation following the horrific attack in Westminster.
“Greater clarity is now developing regarding the casualty figures as we have now collated information from the public and five hospitals - the latest figures I have are that there are currently four dead and 29 people were treated in hospital.
“We are still collating numbers of walking wounded and of those in hospital sadly 7 of them are in a critical condition.
“Tragically the deaths included PC Keith Palmer who was protecting Parliament, and two members of the public - a woman aged in her mid 40’s and a man aged in his mid 50’s.
“The fourth man of course was the terrorist who was shot dead by armed police at the scene.
“Hundreds of detectives have been working through the night and during that time I can confirm we have searched six addresses - and made seven arrests. The inquiries in Birmingham, London and other parts of the country continue.
“It is still our belief - which continues to be born out by our investigation - that this attacker acted alone yesterday and was inspired by international terrorism.
“To be explicit - at this stage, we have no specific information about further threats to the public.
“Clearly our investigation is ongoing - developing all the time - and is focused on his motivation, his preparation and associates.
“I do recognise that the media are making progress in identifying the attacker - I would continue to ask that his name is not published whilst we are at such a sensitive stage in our investigation - and as I state still conducting arrests and searches.
“The large and complicated crime scene remains in place and our work there continues - I would like to thank everyone for their support and patience as we finish this work.
“As people are out and about on the streets of the Capital this morning they will see more police officers on duty - armed and unarmed - and a mix of British Transport Police and the City of London.
“We have cancelled some leave and increased some duty hours and are working to make sure that we can out in force to reassure the public.
“We must not allow terrorists to create discord, distrust and fear.
“The police stand with all communities - later today a meeting of faith leaders will be held here at New Scotland Yard.
“Whilst our work to investigate and understand what happened yesterday continues with vigour - we must also reflect.
“I want to thank the public for their support and all their good wishes - I know it is appreciated by all those men and women who are out there today protecting us.
“Finally, I would also like to ask the public for their continued help and continued vigilance and if you see anything that causes you concern or raises your suspicions do not hesitate to call us - 0800 789 321 - or in an emergency 999.
Casualty Bureau is now open on 0800 056 0944 and 020 7158 0010.
If you are worried about family or friends involved in today's incident please call Casualty Bureau on either number listed above and choose Option 1.
If you were involved in today's incident and are safe, please call Casualty Bureau on either number listed above and choose Option 2.
Demand on Casualty Bureau will be high. Please keep trying. Staff at Casualty Bureau are working hard to speak to as many people as they can.
If you are safe please let friends and family know. This will relieve pressure on Casualty Bureau.
Casualty Bureau is not for general enquiries. Call 999 in an emergency only.
At 22:30hrs on Wednesday, 22 March, Mark Rowley, the national lead for Counter Terrorism Policing and the Acting Deputy Commissioner, said:
"Today, in Westminster we saw tragic events unfold and our thoughts are with those who lost loved ones, who were injured, and all those affected by this attack.
"One of those who died today was a police officer - PC Keith Palmer - a member of our Parliamentary and Diplomatic Protection Command.
"Keith - aged 48 - had 15 years' service and was a husband and a father.
"He was someone who left for work today expecting to return home at the end of his shift and he had every right to expect that would happen.
"I can also now confirm three members of the public also lost their lives in this attack. Specially trained family liaison officers will be deployed to support them.
"And I confirmed earlier, the suspected attacker was shot dead by an armed officer - therefore meaning we now have five people in total who have died.
"I will not comment at this stage on the identity of the attacker, but our working assumption that he was inspired by international terrorism.
"Also, at this stage, but it may change - we believe approximately 40 people were injured, some with serious injuries, including three police officers, two of whom are in a serious condition.
"Our investigation is continuing and is moving at a fast pace this evening - we will work through the night.
"We have hundreds of officers working on this investigation and they are focusing on the suspect's motivation, preparation and associates.
"We are forensically examining a complicated crime scene that covers a wide area.
"As with all investigations of this nature it will take us some time to work through painstakingly all the evidence. Only then will the full picture be known.
"Officers are taking statements from the hundreds of people who were nearby as today's attack unfolded.
"We are seizing CCTV and carrying out a fast-time examination of it.
"The lock down on Parliament has been lifted and we are working hard to reduce the areas we have cordoned off.
"I'd like to thank the public and Parliamentarians for their continued patience as we carry out detailed forensic examinations in the areas.
"The UK threat level has been at 'Severe' for some time and this level will not change.
"We have enhanced the scale of the policing operation to protect our communities across the country.
"As we continue to investigate today's horrific events we do want to reassure the public that police and partners are doing everything possible to protect them.
"As a precautionary measure over the next few days we have increased the number of officers on duty to provide a highly visible, reassurance presence - both armed and unarmed - across the country.
"This will continue for as long as is needed.
"Terrorists have a clear aim and that is to create discord, distrust and to create fear. The police stand with all communities in the UK and will take action against anyone who seeks to undermine society, especially where their crimes are motivated by hate.
"We must recognise now that our Muslim communities will feel anxious at this time given the past behaviour of the extreme right wing and we will continue to work with all community leaders in the coming days.
"It's essential for us to remain vigilant but to also work together - policing and communities - and unite against those who seek, through violence and extremism, to threaten, intimidate and cause fear.
"We ask the public to be alert and to report any suspicious activity to the police by calling 0800 789 321, or dialling 999.
"Whilst today is an incredibly sad and sombre day, especially for the MPS and everyone affected, it is only right that I mention the pride I feel in the swift and brave response from our officers - especially those who without fear for their own safety had to confront the terrorist."
At 17:50hrs on Wednesday, 22 March, Mark Rowley, the national lead for Counter Terrorism Policing and the Acting Deputy Commissioner, said:
"I want to make a statement and will cover three main areas:
= what we know about the incident;
= the ongoing operation; and
= what London can expect over the coming days.
"As you know we have declared this a terrorist incident and the Counter Terrorism Command are carrying out a full scale investigation into the events today.
"The attack started when a car was driven over Westminster Bridge, hitting and injuring a number of members of the public and three police officers who were on their way back from a commendation ceremony.
"The car then crashed near to Parliament and at least one man - armed with a knife - continued the attack, trying to enter Parliament.
"Sadly - I can now confirm that four people have died. That includes a policeman who was protecting Parliament from the attack and one man we believe to be the attacker who was shot by a police firearms officer.
"The officer's family have been made aware.
"At least 20 people have been injured.
"As part of long established and well rehearsed plans, Parliament was locked down and the Met responded in line with our plans for a marauding terrorist attack.
"That response included uniformed and specialist trained firearms officers.
"We have an ongoing operation - and whilst we currently believe there was only one attacker - I am sure the public will understand us taking every precaution in locking down and searching the area as thoroughly as possible.
"I know that the officials working within Parliament and the public completely understand why we need to do this and I thank them for their patience and support.
"This investigation has the full weight and expertise of the Counter Terrorism Command behind it. If there are people who saw the events unfold but haven't yet spoken to police please get in touch with us.
"A crime scene will remain in place in the affected areas in Westminster - it is vital that we carry out a painstaking investigation to recover all possible evidence.
"Looking forward, throughout the rest of the day including when people are commuting home and over the days that follow, the people of London will see extra police officers - both armed and unarmed - out on our streets.
"This includes our officers working longer hours and extra shifts and with our colleagues at British Transport Police and the City of London.
"We can call on the support of the military should we need to at a future point.
"We are also in the process of opening our specialist Casualty Bureau to help those people who are worried that friends or family may have been caught up in the attack.
"We are reaching out and engaging with all communities across London to help reassure them.
"Our strength as a city is our ability to stand together at such terrible times.
"If anyone sees anything suspicious or that causes them concern please do contact us - don't hesitate.
"My thoughts are with all those who have been affected by today's attack - and as a service we have lost one of our own as he acted to protect the public and his colleagues.
"This is a day that we had planned for - that we all hoped would never happen - but sadly it is now a reality.
"The Met Police will continue to do all we can to protect the people of London."
In a statement given today by Commander BJ Harrington at 16:45hrs on Wednesday, 22 March at New Scotland Yard, he said:
"Since 14:40hrs this afternoon (Wednesday, 22 March) the MPS has responded to an incident in the area of Parliament Square, and the Senior National Coordinator has declared this a terrorist incident.
"And although we remain open minded to the motive, a full counter terrorism investigation is already underway - this is led by the Met's Counter Terrorism Command.
"At this stage I will confirm what we know has happened, but I will not speculate.
"We received a number of different reports - which included a person in the river, a car in collision with pedestrians and a man armed with a knife.
"Officers were already in the location as part of our routine policing operation. Immediately, additional officers were sent to the scene and that included firearms officers.
"We are working closely with the London Ambulance Service and the London Fire Brigade.
"I'd like to repeat our request for the public to avoid the following areas:
"Parliament Square; Whitehall; Westminster Bridge; Lambeth Bridge; Victoria Street up to the junction with Broadway and the Victoria Embankment up to Embankment tube.
"This is to allow emergency services to deal with this ongoing incident.
"There is an ongoing investigation being led by the Counter Terrorism Command and we would ask anybody who has images or film of the incident to pass those to police.
"We know that there are a number of causalities, including police officers, but at this stage we cannot confirm numbers or the nature of these injuries.
"Our response will be ongoing for some time as it is important that we gather all possible information and evidence.
"Public safety is our top priority and we are reviewing our policing stance across London and throughout the course of this afternoon there will be additional police and officers deployed across the Capital.
"I would like to ask the public to remain vigilant and let us know if they see anything suspicious that causes them concern and dial 999 immediately.
"The Acting Commissioner Craig Mackey is being treated as a significant witness as he was at the scene when the incident started. Whilst he is not injured, it would be inappropriate for him to talk about the incident at this stage. Ours and his thoughts are with all those involved and those responding to both incidents.
"Anyone with information can also call 0800 789 321."