A woman is fighting for her life after a horrific crash on the M1 this morning between Watford and St Albans.

At 4.30am, a blue Renault Twingo was parked on the hard shoulder near Junction 5 travelling northbound, when a silver 4x4 utility vehicle collided into the back of it.

One of the rear seat passengers – a 19-year-old girl from Barnet – who was trapped in the car, sustained serious injuries and is critically ill in St Mary’s Hospital.

Two other women, one being a 19-year-old from St Albans, were thrown from the vehicle and seriously injured.

A fourth woman was not in the car at the time and was uninjured.

Sergeant Ian Manley from the Road Policing Unit said: “An innocent 19-year-old girl is fighting for her life in hospital and two other young people are being treated for serious injuries.

“We are urgently appealing for any witnesses to the collision or anyone who saw the Twingo or 4x4 utility vehicle prior to the collision to get in touch with us so we can piece together exactly what happened this morning.”

A 28-year-old man from Basildon has been arrested in connection with the collision and remains in custody pending further enquiries.

All three lanes of the M1 northbound were closed until 10am this morning.