Four CRPF personnel were killed and three others injured after their colleague opened fire at them in a camp of the paramilitary force in Chhattisgarh's Sukma district on Monday, a police official said.
The incident took place at around 3.15 am in the camp of the Central Reserve Police Force's (CRPF) 50th battalion in Linganpalli village under Maraiguda police station of the area of the district, located nearly 400 km from the state capital Raipur, Inspector General of Police (Bastar range) Sundarraj P said.
As per preliminary information, constable Reetesh Ranjan fired at his colleagues with his service weapon, an AK-47 rifle, the official said.
The seven injured personnel were immediately shifted to a hospital in nearby Bhadrachalam area of neighbouring Telangana, where doctors declared four of them dead on arrival, the official said.
Those killed were identified as constables Rajmani Kumar Yadav, Rajib Mondal, Dhanji and Dharmendra Kumar, he said, adding that three other injured personnel were being treated at the hospital.
"The motive behind the firing is yet to be ascertained and an investigation is on into the incident," the official said.
Constable Ranjan was immediately held and his interrogation is underway, he said.
In a similar incident of fratricide in January this year, a CRPF jawan was killed and another one injured after their colleague opened fire at them in their camp in the state's Bastar district, police earlier said.
The offender had then tried to commit suicide by shooting himself, they said.
