The police precinct chief in a town in southwestern Colombia was murdered by an unidentified assailant who shot him in the head, officials said.

Juan Carlos Guerrero Medina was killed in La Vega, a town in strife-torn Cauca province, on Saturday.

The 43-year-old officer, who was the father of two children, was on duty when he was killed.

"It was a shot from a sniper," La Vega police inspector Ciro Manzano told reporters.

The municipal government ordered a curfew in La Vega after Guerrero Medina's killing and boosted police patrols. EFE