A motorist driving his family back from a day trip to Cornwall died when he fell asleep at the wheel and veered off the motorway into a tree near Clevedon.

Graham Newman, 51, was just 20 minutes from home when he nodded off and steered his car off the northbound M5 near junction 20 on November 29 last year.

His pregnant girlfriend and two young sons, who had also been asleep on the journey from Redruth to their home in Hill Road, Clevedon, escaped with minor injuries in the crash.

An inquest at Flax Bourton yesterday heard that the force of the impact of divorcee Mr Newman's Renault Laguna estate on the tree caused it to snap off at its base.

Avon deputy coroner Terry Moore was told that Mr Newman's son, Glenn, had earlier woken to find his dad turning up the radio in a bid to stay awake and his partner noticed him wrestling with the steering wheel shortly before the collision.

The inquest was told that Mr Newman later died from multiple injuries, which were described as "non-survivable", at Frenchay Hospital two hours after the accident.

The inquest was told that another motorist travelling on the motorway saw Mr Newman's Laguna go past at about 80mph before veering off the motorway and into the undergrowth. Road traffic accident investigator PC Andrew Grigg said it was likely Mr Newman had woken up and reacted to the fact he was near to a car on his right-hand side by veering off to the left and off the road.

He said Mr Newman suffered serious injuries because the tree had made a "severe intrusion" to the driver's side of the car.

Recording a verdict of accidental death, Mr Moore said: "Mr Newman did something many drivers have done before. They've thought they were nearly home so have continued with their journey. But it appears most likely he had fallen asleep at the wheel. It could have been a micro-sleep or just a case of nodding off."