Detectives investigating an unexplained death in Clapham in 2017 have now launched a murder investigation and believe the murder may be linked to an organised crime syndicate.
A reward of up to £10,000 is being offered by the independent charity Crimestoppers to support detectives.
Police were called at 05:20hrs on 23 November 2017, to reports of a man found unresponsive on Parma Crescent, Clapham Junction, SW11. However they believe the man died some hours before.
Officers along with the London Ambulance Service (LAS) attended and the victim was pronounced dead at the scene.
He was formally identified as 32-year-old Piotr Woroneicki, from Poland.
Piotr was last seen alive at 2332hrs on Wednesday, 22 November 2017, at New Covent Garden Market.
The death was originally investigated by Wandsworth CID as an unexplained death; however following a special post-mortem the cause of death was given as compression to the neck, consistent with the victim being held in a headlock for a prolonged period of time.
Following the post-mortem result being established in July 2018, the case was handed to the Met's Homicide and Major Crime Commands (HMCC) and the investigation is being led by Detective Chief Inspector Mark Cranwell.
DCI Cranwell said: "We have recently taken responsibility for this investigation and I would like to take this opportunity to appeal to anyone who may have known Piotr or have heard anything about his death.
"Any information that you may have could really help this case and we urge you to contact police as soon as possible."
On Wednesday 22 November 2017, police were called by a neighbour to reports of an attempted burglary at Piotr's address on Clapham Common Northside.
Neighbours had told police that at 23:57hrs, two males gained entry to the communal area of the house. CCTV was obtained by attending officers, however it did not show whether the two men entered the victim's apartment or not. The CCTV showed them leaving the communal area shortly after entering.
At 0323hrs on the next day (Thursday, 23 November and the day Piotr's body was discovered), two suspects with a set of keys tried to gain entry to the communal area of the house, however following the attempted break-in from the night before, the locks had been changed and the suspects could not enter the building. It is unknown if they are the same people who tried to enter the building at 2357hrs on 22 November.
On Friday, 24 November, three more attempts were made to break into the building:
At 01:49hrs - Two men gained entry to the building. Access was gained to the flat.
At 07:37hrs - The two suspects returned and gain entry to the communal area of the building only.
At 23:10 to 23:18hrs - The two men returned and once again gained entry to the communal area of the building.
On all five occasions, the suspects appear to differ in descriptions. Officers are keeping an open mind as to whether different people tried to enter the property.
DCI Cranwell adds: "For some reason or another, these people were intent on gaining entry into Piotr's apartment, but the motive as to why remains unclear to us.
"We are releasing CCTV footage of two suspects we want to speak to in connection with the attempted burglary. I'm sure that someone watching and listening to the CCTV videos will recognise their voices or maybe their mannerisms or the way they walk. If you think you do know or recognise them, we'd urge you to call us as soon as possible.
"What makes it even more peculiar is that we know that when officers entered the flat after the actual break in, nearly £100,000 in cash was in the living room along with a significant amount of Class A drugs. Why would someone break into a property and leave that big an amount of cash untouched?
"We are still trying to work out the answer to this question and that is why we think Piotr might have been involved in gangs or organised crime.
"For this reason, we are working alongside our colleagues from the Organised Crime Command to look into whether this murder was a targeted hit."
DCI Cranwell and his team are also working to establish a timeline of events that led up to Piotr Woroneicki's death.
Through CCTV, investigative work and speaking to witnesses, officers have established that:
Piotr left his home address at 21:16hrs on the evening of 22 November 2017.
He was seen with persons known to him in New Covent Garden Market at 22:46hrs.
He was last seen in the market at 23:33hrs
He was found by a member of the public at 0500hrs on 23 November, some hours later, in Parma Crescent, which is approximately three miles in distance from New Covent Garden Market.
DCI Cranwell said: "There are about five and a half hours that Piotr is unaccounted for where we don't know who he may have met with or spoken to and it's crucial that we fill in these missing hours to help solve his murder and convict the person or persons responsible for his death.
"The night Piotr died there was torrential rain that some could describe as 'biblical proportion'. I'm hoping that by mentioning this, it might jog somebody's memory.
"Although I have said that we believe this murder is linked to organised crime, I want to assure anyone with any information that whatever you tell us will be treated with the upmost confidence. You will be helping to take a murderer off the streets and giving Piotr's family and friends some closure in what has been a very tough period."
Anyone with any information is asked to call the incident room number on 020 8721 4054.
A reward of up to £10,000 is being offered by the independent charity Crimestoppers for information that leads to the arrest and conviction of those responsible for Piotr Woroneicki's murder. To give information and qualify, contact Crimestoppers anonymously on 0800 555 111 or through the online form at http://www.crimestoppers-uk.org/