Angus narrowly avoided its second train derailment in six months according to the officer leading the investigation into the latest incident of vandalism.
British Transport Police are appealing for witnesses after a vacuum cleaner hung from a footbridge struck a train as it approached Arbroath on Saturday.
The 6.42 Inverurie to Edinburgh service smashed into the appliance shortly after 8pm, causing it to fall on to the tracks.
The incident follows an object being deliberately placed on the line at Inverkeilor in November that led to the front wheels of a train leaving the track.
PC John McErlane said: “I cannot stress how dangerous this incident could have been.
“Thankfully, on this occasion, the train was not affected and no one was injured, but the next time this happens we might not be so lucky.
“Trains travel at high speeds and there is a very real risk of derailment if they strike objects which could easily fall on to the tracks, as was the case here.”
The driver of the next freight train removed the object from the tracks, near Dens Road, and untied the electrical flex that was still hanging from the footbridge, with help from a member of the public.
Arbroath councillor Robert Spink said: “It’s shocking and irresponsible behaviour. People doing such a thing is thoughtless and it endangers lives.
“If anyone saw a congregation of youths or someone up to no good they should get in touch with police right away.”