Eight people have died after a motorway crash involving two lorries and a minibus.
Thames Valley Police were called shortly before 3.15am on Saturday to the southbound carriageway of the M1 near Newport Pagnell, between junctions 15 and 14.
The vehicles involved in the crash were travelling in the same direction.
It is thought the minibus had travelled from the Nottingham area.
Four people were taken to hospital after the incident in Buckinghamshire, Thames Valley Police said.
Two men have been arrested on suspicion of causing death by dangerous driving and are in custody.
The motorway is closed southbound between junctions 14 and 15 and motorists are being advised to avoid the area.
Chief Inspector Henry Parsons from the joint operations unit for roads policing, said: “Emergency services are continuing to work at the scene and road closures remain in place.
“We are aware there are a number of large-scale events taking place this weekend and this closure is likely to have a significant impact on traffic disruption, so please allow extra time for your journeys.
“Our thoughts are very much with the families of those involved in this morning’s collision and we are currently working to locate and inform their next of kins.”
He asked for any witnesses, or anyone with information, to call the 24-hour Thames Valley Police enquiry centre on 101, quoting URN 214 of 26/8.