South Wales Police are appealing for witnesses to a serious road traffic collision, which occurred at 2:55pm on Sunday 8th April 2018 on the Westbound carriageway of the M4 midway between junctions 34 Miskin and 35 Pencoed.
A white Toyota IQ2 motorcar has left the carriageway to the nearside, collided with trees and overturned. A 15 year old rear seat female passenger has suffered serious head and internal injuries and is currently detained at the University Hospital of Wales Cardiff.
The 18 year old male driver and 16 year old female front seat passenger sustained less serious injuries.
Persons who have not yet passed their details to the Police who witnessed the collision or can provide information concerning the manner of driving of the Toyota motor car prior to the collision are asked to contact 101 quoting 1800121555.
Police would like to thank motorists and the surrounding community for their patience due to the M4 being closed for 3 hours, whilst investigation work was carried out.