Eight members of an indigenous group that took on armed gangs and illegal loggers nearly a year ago have been shot dead in a confrontation in western Mexico, officials said.

The group of indigenous rangers were on their way to clear an area to prevent forest fires when they heard chainsaws and called for reinforcements to confront suspected illegal loggers, Michoacan state secretary Jesus Reyna said late Wednesday.

Eight of the rangers were killed in the subsequent shootout and one of their vehicles was torched, he said.

Last April around 17,000 members of the Purepecha community blocked access to the village of Cheran -- near famous sanctuaries for migrating Monarch butterflies -- accusing organized crime groups of shielding illegal logging.

Illegal loggers have deforested about 80 percent of the region's 30,000 acres (12,000 hectares) of forests in recent years, according to the community.

Michoacan is one of several regions hit by rising violence since the launch of a military crackdown on the country's powerful drug gangs in 2006.