British police were on Tuesday investigating two incidents where objects were placed on railway tracks to sabotage the network in what they believed was deliberate action relating to Britain's exit from the European Union.
British Transport Police (BTP) said the two obstructions occurred on the railway near the town of Yaxley in the eastern count of Cambridgeshire on March 21 and Netherfield in Nottinghamshire on March 27.
Police said staff at Network Rail identified the devices, which were "intended to cause disruption" to train services, and the saboteurs had "put their life at risk" to plant the obstructions.
"This was a serious and deliberate attempt by someone to cause significant sabotage and disruption to Britain's rail network," Assistant Chief Constable Sean O'Callaghan of British Transport Police said in a statement.
"We're are currently keeping an open mind on why someone would put their life at risk to place these items on a live railway, however our early assessment has led us to believe it relates to Britain's exit from the European Union," he said.