The police watchdog is investigating a car crash after officers began following one of the vehicles through Queensbury.
The crash happened around 1.30pm on Brighouse Road at the junction Cross Lane on Sunday September 1.
The collision involved a Ford Focus and a van.
One of the suffered head and leg injuries and was taken to hospital by air ambulance.
The other driver suffered a leg injury.
Road closures were put in place as the emergency services dealt with the incident.
A spokesperson for West Yorkshire Police said: "Police were following a vehicle in the area prior to the collision."
One of the drivers suffered head and leg injuries and was taken in an air ambulance to the hospital.
"Due to the nature of the incident, the Independent Office for Police Conduct has been informed."
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