One person has died and 11 people have been injured after a bus collided with a 4x4 vehicle just north of Ardrossan, North Ayrshire, Police Scotland said.
Two are critically injured, the BBC reports.
Two air ambulances attended the scene.
A Police Scotland spokesman said: "We responded to several reports of a serious road traffic collision at 14.10 on the A78 at Rowan Tree in Ardrossan.
"It involved two vehicles, a double decker bus and a truck. Emergency services are in attendance and diversions are in place."
The incident happened on the A78 in Ardrossan at about 2.10pm.
The Scottish Ambulance Service has called the crash a 'major incident'.