A man has been arrested in connection with the death of a bus driver following a crash in East Ayrshire.
Gordon Stirling, 23, was left fighting for his life following the collision between his Stagecoach single-decker and a white Ford Transit van on the A77 on Monday 14 August.
Mr Stirling, from the Crosshouse area, died at the Queen Elizabeth University Hospital (QEUH) in Glasgow five days later on Saturday 19 August.
The 42-year-old male driver of the van was taken to hospital with serious injuries, where he remains.
The collision happened near the A719 junction between Fenwick and Kingswell that leads south to Galston.
Police Scotland said the force was treating Mr Stirling's death as a murder investigation.
In an update on Thursday, the force confirmed the van driver has now been arrested in connection with the death.
A spokesperson added: "Extensive enquiries remain ongoing to establish the full circumstances of the incident and anyone with information is urged to contact police."