POLICE are trying to track down the driver of a blue van after a crash on the M4 on Saturday.

A black Vauxhall Corsa was travelling westbound at about 12.20pm on Saturday in lane three between Leigh Delamere services and Junction 18 when a blue van, which was travelling in the middle lane, began changing lanes.

It moved into lane three, forcing the Corsa to move towards the central reservation.

The driver of the Corsa, a 25-year-old woman from the Bristol area, then lost control of her vehicle and collided with the central barrier before coming to a stop in the carriageway.

Passing motorists were able to help the driver and the occupants of the Corsa onto the hard shoulder.

The blue van failed to stop at the scene and carried on towards Junction 18, for the A46 to Bath and Stroud.

PC Gary Rosier, of the Roads Policing Unit, said: “Fortunately nobody was injured, but the driver was shaken and in shock due to the collision.

“If anyone witnessed this incident and can provide details of the blue vehicle involved, please contact police immediately. The information you have may be crucial to our investigation.”

Anyone with information should call PC Rosier at Wiltshire Police headquarters on 101, or Crimestoppers anonymously on 0800 555 111.