Updated

The rapid spread of vigilante-style community "self-defense" groups is drawing debate in Mexico, after the latest group popped up with suspiciously sophisticated weapons, printed T-shirts and clothing that doesn't reflect the usual mix of participants.

The new group of vigilantes is armed with some assault rifles, in addition to the mix of shotguns and single-shot rifles used by other similar groups that have appeared recently.

The group appeared this week in Tepalcatepec, in the western state of Michoacan.

A stubborn crime wave has caused groups of farmers in other towns to set up patrols and checkpoints, but they are usually raggedly-dressed farmers, unlike the better-dressed Tepalcatepec vigilantes.

Assistant Interior Secretary Eduardo Sanchez said Tuesday that the government was seeking to negotiate with the vigilante groups.