TWO pensioners from Somerset killed when a tunnel collapsed on them died as a result of an accident, an inquest has heard.

Rosemary Snell, 67, from Misterton near Crewkerne, and Michael Rolfe, 72, from Fivehead, died when the car they were travelling in was engulfed at the Horn Hill tunnel, in Beaminster, Dorset, on July 7, 2012.

After hearing evidence in a day-long inquest at County Hall in Dorchester, senior coroner for Dorset Sheriff Payne said: "Ultimately what happened was an accident."

The inquest also heard that no criminal charges will be brought against Dorset County Council following a police investigation because 'nobody could have foreseen' what happened.

A witness told the inquest earlier that she drove in after the mudslide to be met with 'a wall of mud and water.'

Motorist Patricia Roberts has given evidence about what she encountered when she entered the tunnel that night.

She said she had driven in after another car and told her husband at the time: "I hope they got out okay."

Beaminster fire station commander Mark Greenham has told the inquest that thermal imaging equipment was used inside the tunnel on the night of July 7 - but nothing was found.

The Dorset Fire and Rescue incident log about the mudslide was closed in the early hours of July 8, the inquest heard.

But the investigation was re-opened on July 16 after concerns were raised over the whereabouts of the couple.

Diggers were used to excavate the car, which commander Greenham said was 'full of mud.'

He has been questioned by a member of Rosemary Snell's family as to why there was such a delay in the search.

Commander Greenham replied that the position of the fire service is not to look unless there is a suspicion someone could be inside the mudslide and he is not aware of any technology which could have detected the bodies.

The main A3066 road from Beaminster was closed at the tunnel for more than a year after the incident so that stabilisation work could be carried out.

David Clinton, who prepared a report for Dorset Police, said that while it is possible the removal of trees contributed to the landslip, it is unlikely to be a significant factor.

Others who have so far given evidence include Mr Rolfe's son, who described his father as a talented doctor who worked in Africa specialising in the study of AIDS.

Rosemary Snell's friend Carole Walker said that Rosemary had described Michael as her 'soulmate.'