The Pakistani Taliban has released a graphic video purportedly showing militants executing 16 Pakistani police officers who were captured in the country's northwest last month.

The video, which was posted on a website, shows the tribal police officers, wearing traditional baggy shirt and pants , lined up with their hands tied behind their backs.

The Taliban militants, whose faces are covered, accuse the policemen of being enemies of God and of killing six children in the northwestern region of Swat Valley. The militants then open fire on the officers, killing them.

Pakistani army spokesman Major General Athar Abbas confirmed the contents of the video Monday. Abbas said the policemen were captured by militants who entered Pakistan's Upper Dir tribal region from Afghanistan on June 1.

At the time, Pakistani government officials said more than 400 militants crossed into Upper Dir from Afghanistan's Kunar province. At least 27 security personnel and 35 militants were killed in the ensuing clashes. The Pakistani Taliban claimed responsibility for the raid.

Pakistan's government lodged a protest with Afghanistan and called on Afghan and NATO forces to crack down on insurgents on the Afghan side of the border.