Investigators have clawed for clues, scouring cabins for fingerprints that match no one and chasing reports of brief encounters only to come up short, always a step behind the mysterious recluse.
They've found abandoned camps, dozens of guns, high-end outdoor gear stolen from the homes and trash strewn around the forest floor.
But the man authorities say is armed and dangerous and responsible for more than two dozen burglaries has continued to outrun the law across a swath of mountains not far from Zion National Park. He's roamed across 1,000 square miles of rugged wilderness where snow can pile 10 feet deep in winter.
And while there have been no violent confrontations, detectives say he's a time bomb. Lately he has been leaving the cabins in disarray and riddled with bullets after defacing religious icons, and a recent note left behind in one cabin warned, "Get off my mountain."
"You wouldn't want to come across that guy," said Iron County Det. Jody Edwards, who has been working the case since 2007.
Theories about his identity have ranged from a 42-year-old man on the FBI's Most Wanted List sought for the 2004 killing of an armored-truck guard in Phoenix to a castaway from the nearby compounds of the Fundamentalist Church of Jesus Christ of Latter Day Saints, the polygamous sect run by jailed leader Warren Jeffs.
kinda looks like robert fisher FBI top 10 (Killed wife and kids)
The FBI recently discounted the theory that the man was their fugitive after authorities got the first pictures of him from a motion-triggered surveillance camera outside a cabin showing a sandy-haired man in camouflage on snowshoes, a rifle slung over his shoulder. The photos were captured sometime in December.
"We believe that is not Jason Derek Brown," FBI special agent Manuel Johnson told The Associated Press.