Michael Maher, 30, was arrested Saturday, The Denver Post reported. The charges include stealing fire supplies and obstructing a peace officer as well as impersonation.
Brian Kozak, the former police chief in Avon, Colo., said Maher, who actually worked for a tree service, often told people there he was a firefighter, the newspaper reported.
"He likes to seek attention that way. It's probably the way he tries to get close to people," Kozak said. "They trust him if he's a firefighter, but his motives are kind of creepy."
Kozak obtained a restraining order after Maher kept showing up at his daughter's employer. When he was 21, Maher was charged with sexually assaulting a 14-year-old girl, although he eventually pleaded guilty to a misdemeanor, the report said.
Officials at a Buddhist retreat center said Maher showed up there Friday afternoon, said he was a firefighter and offered to help them get ready in case the High Park fire headed there way.
"He knew his stuff. He gave helpful information," said Zane Edwards, the center's health and safety officer. "He had with him maps. A radio. He could have genuinely wanted to help us out."