Montana authorities are on a manhunt for an "extremely dangerous" former militia leader who triggered a shootout with cops and fled into the wilderness with a cache of weapons.

David Burgert, 47, a former head of a violent anti-government militia group, traded gunfire with Missoula County deputies along a logging trail after a slow speed car chase near Lolo, Mont., on Sunday, cops said.

The ex-Marine and backwoods survivalist started the 30-mile pursuit after cops tried to pull him over for driving wildly at a rest stop, authorities said.

After ignoring repeated commands to surrender, Burgert pulled his Jeep Cherokee onto a remote side road and started shooting, cops said.

Officers returned fire, but Burgert managed to flee into the woods on foot with a pack of gear, Missoula County Undersheriff Mike Dominick said.