British Transport Police have issued a fresh appeal for information regarding November’s train derailment at Inverkeilor.
Officers think an object was placed on the line deliberately, putting the lives of the 36 passengers and train driver on board the Edinburgh to Aberdeen CrossCountry train at risk.
The train’s front wheels left the line as it was passing through Inverkeilor at 9.45am on November 4 but luckily no one was seriously hurt.
The rail industry subsequently put up a £25,000 reward for information which is yet to be claimed.
Police believe tracing a group of youngsters seen near the tracks on the night before the incident may be vital to solving the case but as yet no arrests have been made.
Councillor Bob Spink, who lives in the village, thinks the group of youths may have been from outwith the area.
He said: “People in the village are very socially aware. I’ve worked here for 32 years and I know a lot of them pretty well and most people always know what’s going on.
“If they had seen anything suspicious they would have told the police but there hasn’t been a cheep. It was a shockingly dangerous episode.”
Police say the group they are seeking to identify consisted of four people who ranged from 5ft to 5ft 6in.
One member was wearing a grey or light-coloured hooded top and trousers. It is not known whether they were male or female.
The youths were seen walking towards Bryanton House, just off the A92, prior to the bonfire at Inverkeilor on the night before the derailment.
Police have also asked anyone who took photographs at the bonfire that night to come forward.
The investigation is being conducted by British Transport Police, the Rail Accident Investigation Branch and the Office of Rail Regulation.