A RAILWAY historian has added his voice to the concerns about the building material used at the collapsed Gerrards Cross Tesco tunnel.

John Healy, from Chesham, said it could have been a lot worse and likened what happened to the 1960s Welsh tragedy at Aberfan, where slag material buried a school and killed more than 100 children.

Mr Healy said: "Had the caving in happened in rush hour, then debris could easily have buried a passenger train, echoing on a smaller scale one of Britain's worst disasters.

"Let us hope that this scenario will not be repeated, as a result of further tunnel collapse or the new superstore caving in while full of people. Is it not time for Tesco, in accordance with residents' wishes, to pack up and leave Gerrards Cross altogether?"

A Tesco spokesman said: "We are now looking at design and construction issues with the other parties on site to find a solution to get on with the work. We are keeping safety in mind as always."