Train passengers were lucky to escape unhurt after concrete blocks were placed on tracks near Peterborough.
Officers are appealing for anyone who may have any information after a train struck concrete blocks that had been placed on the tracks at about 5.30pm on Saturday, October 10.
The train struck concrete blocks placed on the tracks under Frank Perkins Parkway Flyover on the March Line in Peterborough.
Luckily no-one on the train, a Cross Country Service travelling between Peterborough and Kings Dyke, was injured and no significant damage was caused to the train.
PC Glen Fryer said: “The train struck a number of concrete troughing lids which had been placed across the tracks. Fortunately no-one was injured which was extremely lucky. However this type of reckless behaviour is criminal and dangerous and we would like your help in tracing those responsible.
“A group of five youths, between the ages of 9 and 11 were seen running back and forth across the tracks in the same location prior to the incident. They were also seen running down a footpath adjacent to the tracks just after and we believe this may be the group responsible.
“If you witnessed the incident or know who the group may be, please contact us”.
If you know the man or have any further information which could help, please contact BTP on 0800 405040 or text 61016, quoting reference MSUB/B4 of 9/11/2015. Information can also be passed anonymously to independent charity Crimestoppers on 0800 555 111.