A Central Industrial Security Force constable opened fire at four fellow guards at in Aurangabad, Bihar, on Thursday. There are conflicting reports on how many of them were killed in the incident – while some say all four were killed, a PTI report says three troops died and one was in a critical condition. At least two of the CISF officers were confirmed to have died on the spot.

The incident took place at the Nabinagar power plant and is believed to be a case of fratricide, according to Hindustan Times. The accused – identified as Balveer Singh – has been arrested and is being questioned.

Aurangabad Superintendent of Police Dr Satyaprakash told Hindustan Times that they were trying to find out more about the shooting. The senior policeman told PTI that Singh had lost his temper following a tiff over leave. “Preliminary information states that Singh opened fire on his colleagues using his service rifle in an alleged fratricide incident,” he said.

CISF Director General OP Singh (pictured above) is headed to the unit to look into the incident. The Home Affairs Ministry, under which the paramilitary force functions, has sought a report on the shooting.

The four troops who are shot at were identified as head constables Amarnath Mishra and Bacha Sharma, Assistant Sub Inspector GS Ram and Havaldar Arvind Ram.