LASHKAR GAH, Afghanistan, March 28 (Xinhua) -- Five police were killed and two others injured after a group of armed militants attacked a security checkpoint in Kajaki district of the southern Helmand province on Thursday, police spokesman for the restive province, Zaman Hamdard said.

The clash, according to the official, happened in the wee hours of Thursday in Pozak area of Kajaki district and the militants fled away after killing five police on duty.

Two more police personnel sustained injuries in the firefight, the official said.

Taliban militants, who are active in parts of the restive poppy growing Helmand province, haven't commented yet.