A double-decker bus carrying 85 passengers has crashed on the M77 in Ayrshire, injuring four people.
The X77 Ayr to Glasgow Stagecoach service is thought to have hit a vehicle at the side of the northbound carriageway near junction 7.
The bus driver and two passengers were taken to hospital along with a 44-year-old man who is seriously ill.
The accident happened at about 1415 BST causing major tailbacks to the Meiklewood roundabout.
The casualties were taken to Crosshouse Hospital in Kilmarnock for treatment.
A Stagecoach spokesman said: "The driver of the X77 service, which was carrying around 85 passengers, suffered a head injury. A number of passengers have also been injured.
"The coach remained upright following the incident and passengers were able to leave the vehicle through the normal entrance.
"Our first thoughts are with those who have been injured in the accident.
"We have also organised replacement coaches to take passengers not requiring medical treatment to their destination.
"We are assisting police in any way that we can with their investigation into the accident."
Insp Steven Meikle said Strathclyde Police's road traffic division was investigating the crash and urged witnesses to come forward.