A number of officers have been injured following a police operation in Barnet.
At around 13:50hrs on Wednesday, 23 September, officers attended an industrial area in Dale Close, Barnet, to execute a drugs warrant as part of a proactive operation.
As they executed the warrant, officers were injured by a suspected corrosive substance.
Full enquiries into the exact circumstances continue.
11 firearms officers are believed to have suffered injuries and are receiving medical treatment have all gone to hospital. We await an assessment of the extent of these injuries. However none are believed to be in a life-threatening condition.
We are working to inform their families.
Four males were arrested on suspicion of drug offences at this stage.
They have been taken to hospital having also suffered injuries related to the substance. Their conditions are not believed to be life-threatening.
Officers remain at the scene and enquiries continue.
London Ambulance Service and London Fire Brigade colleagues are also in attendance.
The Met's Directorate of Professional Standards have been informed as is routine.
The incident is not being treated as terror-related.
Chief Superintendent Roy Smith - BCU Commander for Harrow, Brent and Barnet - said: “I am extremely grateful to colleagues from our Specialist Firearms Command who put themselves at risk to protect our communities, and colleagues from London Fire Brigade & London Ambulance Service who came to their assistance using our well established protocols for dealing with this type of incident.
"I’d like to reassure the local community that there is no ongoing risk to the public and local officers will remain on patrol in the area to provide reassurance."