As the investigation into the deadly firefighter ambush in Idaho over the weekend continues, police are still trying to piece together why suspect Wess Roley allegedly instigated the attack, a source familiar told ABC News.

Wess Roley, 20, was living out of his vehicle and his former roommate said he shaved off his long hair and started to "kind of go downhill.”

The suspect, who died on Sunday and was found with a firearm nearby, was a 20-year-old man, according to a law-enforcement official.