Two men have died and one woman is in a critical condition after a car crash on the M4 in Wiltshire.

The accident happened on Monday at 2200 GMT on the westbound carriageway between Swindon and Chippenham.

The 46-year-old Bristol woman was pulled from the burning car by passing motorists and airlifted to the city's Frenchay Hospital.

The woman's husband and a second man from Middlesex died in the accident.

'Rescue attempt''

Police believe the Middlesex man was driving the car and that he lost control.

The car, a green Mercedes estate, crossed two carriageways between junction 16 and 17 before hitting the central barrier.

It then catapulted into a field and caught fire.

Sergeant Day of Wiltshire Police said passers-by risked their lives in a rescue attempt.

"There were several members of the public at the scene and we know that at least two of them attempted to get the people out.

'Fog'

"They removed the lady passenger and tried to go back. But by then, the flames were too great."

One of the men was trapped in the car and died as a result of the flames. The second man was thrown from the car and died from his injuries.

Police have ruled out fog as a potential cause of the accident.

All three lanes of the motorway have now been reopened.