More than 50 detonators in two boxes were found abandoned on a platform at Kalyan railway station in Thane district on Wednesday, a Government Railway Police (GRP) official said.
The official said the boxes were spotted by the GRP lying unattended on the platform No. 1 of the usually crowded station on the Central Railway (CR) route following which a dog squad and Bomb Detection and Disposal Squad (BDDS) personnel were immediately called to the spot.
The BDDS team took the boxes into custody and on opening found as many as 54 detonators (a device containing small amount of explosive) inside them, he said.
The Kalyan GRP has launched a probe though they were yet to register a case in connection with the seizure, said the official.
Senior police officials, including Thane city cops, visited the spot where the detonators were found.
Usually, detonators are used in Thane district for illegally catching fish in lakes and also for carrying out blasting operations in quarries.
Detonators are used to send shock-waves through the water, stunning or killing fish which are then collected.
Kalyan railway station on Mumbai city's outskirts serves commuters of both long-distance as well as suburban trains and is usually very crowded.