A ninth member of the unit has been found alive with wounds to his head. The bodies of some of the dead officers are reported to have been mutilated.

The police patrol was investigating a murder when it was ambushed.

Guerrero state has been the focus of drug-related violence that has killed more than 28,000 Mexicans since 2006.

The nine agents from the federal investigative police had travelled to Teloloapan district after a man was reported shot dead.

As they went in pursuit of the suspected killers they were stopped by a large group of gunmen.

Two officers were found shot dead close to where they were abducted. The other six were found about 15km away after a search by police and military troops.

Teloloapan is close to the mining town of Taxco, where, in May, 55 bodies were recovered from an abandoned silver mine that it is believed drug gangs were using as a mass grave.

It has also been the scene of a violent struggle between rival drug gangs for control of smuggling routes to the US along the Pacific coast.