A WOMAN remains in hospital after an “extremely serious collision” which forced the A1(M) to shut for four hours.

A man and a woman were travelling northbound in a silver Vauxhall Corsa when the car left the road just after junction 8 for Stevenage at about 1.55pm on Sunday.

It is not yet known what caused the crash, which saw the car roll over before stopping in a field opposite the motorway.

The man and woman involved were taken to Lister Hospital in Stevenage, where the female passenger remains in a serious condition.

The A1(M) was subsequently closed between junction 8 and junction 9 for Letchworth Gate until about 6pm.

Police constable Adrian Parke from the Bedfordshire, Cambridgeshire and Hertfordshire Roads Policing Unit said: “This was an extremely serious collision which has resulted in one person in hospital in a serious condition. We are determined to trace anyone who may have witnessed this collision to get in touch with us.

“I would urge anyone who may have seen either vehicle prior to the collision taking place to call us as a matter of urgency.”

Anyone with information is asked to contact Pc Parke on non emergency number 101 or call Crimestoppers anonymously on 0800 555 111.