The army said four troops were killed in early Wednesday shooting at a military facility in the Indian border state of Punjab, and that the gunmen were being sought.

An unknown number of gunmen were at loose at the base in Bathinda city, according to a defense source who declined to be named due to the sensitivity of the situation.

According to an army statement, four troops died as a result of bullet wounds received during the fire incident in the early hours of Wednesday morning. The statement made no mention of the circumstances or who was to blame for the occurrence.

The incident was “not a terror attack”, and took place in a canteen, a senior police official in Punjab, S.P.S. Parmar told Reuters.

The base was sealed off and a joint investigation with the local police was on, the army statement said, adding that no other injuries and damage to property was reported.

“All aspects including the possible case of involvement of an (assault) rifle along with 28 rounds reported missing two days back are being ascertained,” the army said.

Visuals from Reuters partner ANI showed barricades placed on the road outside the gates of the military station and security personnel deployed outside the boundary wall.

The incident took place at 4:35 a.m. (2305 GMT Tuesday), an earlier army statement said.

The military base, about 280 km (175 miles) northwest of New Delhi, houses mostly families of soldiers. The border with Pakistan is about 100 km (62 miles) west of Bathinda.