Dale Cregan trial: Prison vans collide going to court in Preston
Two prison vans transporting defendants to the Dale Cregan trial have been involved in a collision in Lancashire.
The crash happened at 09:40 BST. A decision was taken to continue to court, said the North West Ambulance Service.
Four prison officers suffered minor injuries and were taken to hospital for treatment. One prisoner was injured.
Dale Cregan is on trial with nine other defendants in connection with the deaths of Mark and David Short.
On Wednesday, Cregan admitted the murders of the father and son in separate attacks in Greater Manchester last year.
He had already pleaded guilty to the murders of PCs Fiona Bone and Nicola Hughes but denies the attempted murder of Sharon Hark.
The crash occurred close to the the roundabout at the exit of junction 31A of the M6 northbound, police said.
Lancashire Police said they were investigating the circumstances of the collision.
The trial continues.