By Staff Reporter (staff@latinospost.com) | First Posted: Mar 12, 2014 09:39 AM EDT

A leader of armed vigilantes who are helping federal security forces combat a violent drug gang in western Mexico has been arrested on suspicion of murder, which could test the fragile peace the government has built there.

The attorney general's office in the state of Michoacan said late on Tuesday it detained Hipolito Mora on suspicion that he and others in his group took part in the killing of two men whose charred remains were found on Saturday.

The government said this week that tensions have been rising between some of the vigilante groups in the state.

Local media said one of the dead men belonged to another vigilante group. A federal official declined to confirm this, saying the incident was still under investigation. Mora could not be reached for comment.

Mora is one of the most prominent leaders of "self-defense groups" that have weakened the Knights Templar, a drug cartel which has had much of Michoacan in a firm grip over the past few years.

The government formed an uneasy alliance with the vigilantes after they overran a number of Knights Templar strongholds in Michoacan at the start of 2014, and has since captured one of the cartel's leaders and killed another.

Locals believe the vigilantes may have been infiltrated by organized crime groups, however, raising doubts about how sustainable the alliance is.

Michoacan has become a test case for President Enrique Pena Nieto's ability to crush the gangs in Mexico. More than 85,000 people have died in cartel-related violence since Pena Nieto's predecessor Felipe Calderon launched a crackdown seven years ago.

(Reporting by Dave Graham and Lizbeth Diaz; Editing by Sonya Hepinstall)

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