The tragedy, which killed a man, his wife and his brother at Halkirk in Caithness, has led to renewed calls for safety to be improved at crossings after it was revealed it had no barrier.

Angus MacKay and his wife Margaret, both 81, of Inverness, and his brother Donald, 66, were travelling in the Nissan Almera which was struck by the Inverness to Wick train at the village’s level crossing, around 2.10pm hours on Tuesday 29 September 2009:

Mr MacKay was driving the car and Mrs MacKay was in one of the back seats. Donald MacKay, of Latheron in Caithness was the front seat passenger

In a statement, issued through British Transport Police, Mr and Mrs MacKay’s son Donald said on behalf of the family: “We will always remember them and they will always be in our hearts and they will be deeply missed.”

They asked for their privacy to be respected as they came to terms with the devastating loss.

British Transport Police said a joint investigation is continuing with Northern Constabulary and they are working closely with officials from the Rail Accident Investigation Branch to understand the circumstances surrounding the incident on Monday.

They said there appeared to be no suspicious circumstances surrounding their deaths and a report has been submitted to the local Procurator Fiscal.