Three people have died and two drivers have been arrested after a serious collision involving a lorry, a minibus and a car on the M25 in Essex.
A fourth person is in hospital with life-threatening injuries after the crash, which occurred near Waltham Abbey around 6.15pm on Monday and caused lengthy traffic delays.
Essex Police said in a statement the collision occurred between junctions 27 and 26 of the anti-clockwise carriageway, with two drivers arrested on suspicion of causing death and serious injury by dangerous driving.
The M25 remains closed between those two junctions, with Highways England hoping to have it reopened before 2am on Tuesday.
Police said they were eager to trace the movements of all three vehicles – a Ford Mondeo, a minibus and a lorry – leading up to the collision.
They are urging witnesses with dashcam footage to submit a report at www.essex.police.uk, or call 101 citing incident 972 of Monday, August 23.
Information can also be given to Crimestoppers anonymously on 0800 555 111 or https://crimestoppers-uk.org.
Detective Sergeant Steve Holmes, from the Serious Collision Investigation Unit, said: “This evening has been incredibly challenging and we are continuing to work as quickly as we can to piece together exactly what led to this tragic incident.
“My thoughts, and those of all officers on scene are with the families of those who lost their lives this evening.
“At present, two drivers have been arrested on suspicion of causing death by dangerous driving and on suspicion of causing serious injury by dangerous driving.
“I need anyone with further information to come forward.”