The detonators were taken from a SkyBlue Rail van in Willenhall.

The haul included six fog signals which contain explosives and give an audible warning to the driver as the train passes over the device that workers are on the line ahead.

Sgt Wayne Eley said: “These fog signals are specialist equipment that are of no use or value to those who have stolen them.

“They can be extremely hazardous to anyone who isn’t professionally trained in their use and we are very keen to return them to the railway contractor.

“If you know who has them, have been offered the items for sale or simply wish to leave them somewhere anonymously for collection – please let us know.

“Our main priority is taking them out of the community and out of harm’s way.”