More than a dozen Afghan policemen have defected to Taliban in Farah province in the western part of the country, in what is believed to be the largest such defection by officers.

According to reports, 13 junior policemen under the command of a man named Mirwais joined the other side on Taiwan and took with them heavy weaponry, radios and police vehicles including Humvees.

Intelligence officials allege that Mirwais poisoned seven other policemen who refused to defect.

The Farah area had witnessed a decrease in Taliban activity until recently. The defection of a police commander presents a grave security threat to a country already reeling from more than ten years of war.