At least two people were reportedly killed on Friday while making crude bombs in Dubrajpur town of West Bengal's Birbhum district.
"Two persons killed in blast in Birbhum district of West Bengal," PTI quoted SP Mukesh Kumar as saying.
The explosion took place early on Friday and the police have recovered a huge amount of explosives from the site.
West Bengal has been under the scanner since October 2014 after an explosion was reported from Burdwan district on 2 October. The blast had reportedly killed two people who were making bombs. The West Bengal police had found that the deceased were members of Jamaat-ul-Mujahideen Bangladesh (JMB). Connections with al Qaeda were also suspected as police had recovered some leaflets and papers with names of al Qaeda chief Ayman al-Zawahiri.
"In the pamphlets, we found words and phrases like 'mujahid' and 'salaam to our brothers in Chechnya'. We also found the name of Zawahiri (the Qaida leader) in some pamphlets," The Telegraph had quoted a police officer as saying in October 2014. A series of bomb blasts were also reported later that month from West Bengal's Malda district.