Police are appealing for information following a serious road traffic collision involving a motorbike and double decker bus in Halifax.
At around 6.58pm, Tuesday 10th May night, a motorbike was sighted by officers travelling on Thorpe Street towards Boothtown Road, which failed to stop for officers when requested.
The motorbike was then in a collision with a bus almost immediately afterwards near to the junction of Boothtown Road.
The motorbike rider, a teenage male, suffered serious injuries and was taken to hospital where he remains in a critical condition.
Road closures were put in place at the time on Boothtown Road but have since been removed.
Anyone with information which may assist with ongoing enquiries is asked to contact Calderdale District Police on 101 or via the 101LiveChat function on the website, quoting log 1380 of 10th May.
Due to the involvement of a police vehicle in the circumstances leading up to the collision, the incident was referred to the Independent Office of Police Conduct.