POLICE have renewed their appeal for witnesses to come forward after a woman was killed in a head on collision on the M4 on Sunday night.

The 41-year-old from Gloucester was driving an Audi A3 the wrong way down the eastbound carriageway when she hit several cars before colliding head on with an Audi A4 at about 10.40pm.

She was pronounced dead at the scene while the 35-year-old driver of the A4 was taken to Southmead Hospital in Bristol with serious leg and pelvic injuries.

The incident took place between junction 17, Swindon West, and 16 for Chippenham and it is unclear how the driver managed to get on to the wrong carriageway.

The motorway was closed until the early hours of Monday morning while forensic teams carried out investigations.

PC James Trafford, of the roads policing unit, said: "We are continuing our enquiries in relation to this incident and would like to thank the members of the public who have helped with our investigation so far.

"We would appeal to anyone who may have witnessed the collision, anyone who may have seen the Audi A3 prior to the collision, or anyone who may have dashcam footage who has not already made contact with police to get in touch."

Police are appealing for anybody who witnessed the incident to come forward by calling 101 and asking for the TriForce investigations unit.