A Brazilian police inspector shot and killed four colleagues Sunday at the station where they worked, according to the department.

The incident occurred early Sunday morning at a Civil Police station in the city of Camocim, in the northeastern state of Ceara, the force said in an Instagram post.

The suspect shooter, who was off duty at the time, fled in a police vehicle and later surrendered at a Military Police station, a local security official told the G1 news outlet.

The situation — including any potential motive — remains under investigation. The mayor of Camocim — which is approximately 350 kilometers (220 miles) from the state capital of Fortaleza — declared three days of mourning in remembrance of the victims. (AFP: Text, Excluding Headline)