British Transport Police (BTP) has issued a warning after a number of detonators were stolen from a railway line in Sunderland at the weekend.
The detonators are designed to emit a loud bang on impact. In this instance, the devices were used by rail staff to warn maintenance workers of approaching trains. Officers said six were removed from the line near Villette Road between 10:55pm on Saturday, and 1am on Sunday.
The detonators are described as small discs, approximated 5cm in diameter with two lead strips on either side.
PC Mick Proudfoot, of British Transport Police, said: "They could be very dangerous in untrained hands, particularly young children or teenagers who may see them as a source of fun or entertainment.
"Only a few weeks ago a teenager from Essex sadly lost their sight after a detonator accident so I can't emphasise the dangers enough.
"We are obviously concerned for the safety of the individuals who have the detonators, regardless of their age, and I would urge anyone who has information that could help us with our enquiries to contact us as soon as possible."
Anyone with information is asked to contact British Transport Police on Freefone 0800 40 50 40.