A convict in the 1993 Mumbai serial bomb blasts case was beaten to death on Sunday by a group of five inmates at the Kalamba Central Jail in Maharashtra’s Kolhapur district, The Times of India reported.

Fifty-nine-year-old Munna, whose aliases were Mohammed Ali Khan and Manojkumar Bhavarlal Gupta, was allegedly attacked after a quarrel broke out between him and the five men when he had gone to bathe at a water tank in the jail premises, The Indian Express reported citing unidentified police officials.

Munna was allegedly beaten to death with a manhole cover. The incident took place some time after the attendance of all inmates was taken at 6.30 am, according to The Indian Express.

Deputy Inspector General of Police Swati Sathe said that the reason behind the attack was yet to be determined, The Times of India reported.

The five men were identified as Deepak Netaji Khot, Saurabh Vikas Siddha, Pratik alias Pilya Suresh Patil, Sandip alias Bablu Shankar Chavan and Ruturaj Inamdar. They were undertrials facing charges under the Maharashtra Control of Organised Crime Act, Kolhapur Superintendent of Police Mahendra Pandit said, The Indian Express reported.

Police inspector Sanjivkumar Zade said that a first information report had been registered against the five men under sections of the Indian Penal Code pertaining to murder and causing disturbance in government work.

Zade also said that prison staffers had tried to stop the five men from attacking Munna. “But the assailants manhandled the jail staffers and committed the murder,” he said.

Munna was serving life imprisonment after being convicted for his role in the bomb blasts that took place in Mumbai on March 12, 1993, killing 257 persons. He had completed his original 14-year sentence, but the Supreme Court revised this to a life term in 2007, The Times of India reported.

Munna was accused of escorting Tiger Memon, the main person accused in the case, from Mumbai to Raigad to receive RDX, an explosive chemical compound, and arms ahead of the blasts. He also helped bring the goods into Mumbai city.