It was a weekend of chaos for motorists on the M4 with seven separate smashes, one of which left a man in a life-threatening condition.

Icy conditions led to four crashes in the space of two hours along a two kilometre stretch of the motorway.

And following an incident on Friday night a Bristol man is seriously ill in hospital.

Eight vehicles were involved in the four smashes between the Avon Bridge and junction 17 westbound of the M4 between 8-10am yesterday as well as another incident on the M4.

Acting sergeant John Webb said the police were on the scene from 8am till 11.30am dealing with collisions. He said: "I would imagine seeing the police and deciding to brake with the road conditions may have caused some of them."

An ambulance attended one of the four smashes and the driver was taken to the Great Western Hospital with minor injuries.

And following the two-car collision on Friday night, a man is described as in a life-threatening condition with serious head injuries.

Police were called to the M4 at 10.40pm on Friday after a blue Ford Escort and a red Renault Laguna crashed when going east between junctions 15 and 16.

The Escort came to rest across two lanes at right angles to the traffic while the Laguna left the road, travelled down a grass slope and came to rest against some trees.

Other motorists on the road stopped and pushed the Escort off the road.

The driver of the Escort a 34-year-old man from Berkshire was uninjured.

Five men from Bristol were travelling in the Laguna.

The man with serious head injuries, who was a rear seat passenger, was taken first to the Great Western Hospital and later transferred to a specialist unit. Another man suffered abdominal injuries while the other three men had lesser injuries.

One lane of the motorway had to be closed for several hours after the incident.

The cause of the accident is not yet known and police are investigating.

A broken-down lorry also led to lengthy delays on Friday.

The incident happened on the westbound carriageway between junctions 16 and 17 at about 4pm.

It is thought the lorry's brakes locked after debris severed one of its cables. Police removed the lorry within an hour.

l Police are looking for witnesses to the crash. Anyone with any information should call Swindon Police on 01793 528111 and ask for PC1058 Glen Powell.

Isabel Field