A Central Industrial Security Force (CISF) constable killed three senior colleagues and injured one in "deliberate" firing with his service rifle in Bihar's Aurangabad district on Thursday, an official said.
The incident was reported around 12.30 p.m. during changing of shift at a CISF unit deployed at Nabinagar in the district.
"Constable Balveer Singh deliberately opened fire from his service rifle during B shift briefing near the quarter guard, where he had been on duty from 9 a.m. to 12 noon," a CISF official told IANS.
Two head constables were killed on the spot while an Assistant Sub Inspector succumbed to his injuries in a hospital, said the official, adding another head constable was critically injured.
Singh, a resident of Uttar Pradesh's Aligarh, has been taken into custody, the official said.
--IANS
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