A northwest Idaho community is reeling after a 20-year-old man was suspected of fatally shooting two firefighters and injuring another after intentionally starting a fire to ambush them.

Battalion Chiefs John Morrison and Frank J. Harwood were killed in the June 29 attack on Canfield Mountain in Coeur d’Alene.

Firefighter and engineer David Tysdal was seriously wounded and remains in hospital.

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Authorities identified the suspect as Wess Roley.

Kootenai County Sheriff Bob Norris said it appeared he had been living in his car, and authorities did not know why he was in the area.

Roley, who dreamed of becoming a firefighter himself, was found dead on the mountain from a suspected self-inflicted gunshot wound.

Who is Wess Roley?

Norris said Roley grew up in an arborist family, telling reporters that the family climbed trees.

An arborist is a trained professional in the care and management of trees and woody plants.

“We did have reports that he was shooting at first responders via a tree,” Norris said.

Court documents show that Roley may have had a tumultuous childhood.

In 2015, his mother, Heather Lynn Cuchiara, sought an order of protection against her then-husband and Roley’s father, Jason Roley.

The documents allege that Jason Roley pushed her to the ground and made threatening remarks about “waiting outside with a sniper rifle”.

Cuchiara expressed concerns about drugs and two guns in his home and asked that the order of protection include Wess Roley, who was about 10 years old at the time.

Authorities said the 20-year-old had ties to California, Arizona and Idaho. It is unclear why he was in the area.

Kootenai County Sheriff’s Office and the Coeur d’Alene Police Department had five interactions with Roley, according to Norris.

He described the interactions as “very minor in nature” and said they had to do with trespassing and “some welfare checks”.

One welfare check was made after Roley’s car was found parked outside a restaurant “where he appeared to be residing,” Norris said.

“He was asked to leave and he complied,” he told reporters.

None of the welfare checks came from relatives, according to the sheriff.

Roley did not have any criminal history.

In a statement released Monday night via an attorney, the Roley family said they “do not understand why this happened or how this came about.”

“There are no words that can suffice for this tragedy and the infinite losses suffered by those affected by this shooting,” they said.

“Our hearts and spirits are broken for the lost and hurting, and for our own loss as well.

“We intend to fully cooperate with authorities in seeking answers.”

Kootenai County Fire & Rescue Battalion Chief Frank J. Harwood and Coeur d’Alene Fire Battalion Chief John Morrison were killed. Credit: Supplied

Kootenai County Sheriff Bob Norris speaks after a shooter ambushed and killed multiple firefighters responding to a wildfire. Credit: Lindsey Wasson/AP

Roley’s grandfather, Dale Roley, said he believes “something must have snapped” for his grandson to have committed such a heinous act, especially against firefighters, because he always dreamed of becoming one.

“He actually really respected law enforcement,” he told NBC News.

“He loved firefighters. It didn’t make sense that he was shooting firefighters. Maybe he got rejected or something.”

Authorities said they have not found a manifesto and do not have any indication of a motive.

Norris said investigators are aware of Roley’s interest in becoming a firefighter but have not found any applications with local agencies or a statement of intent.

Dale Roley said his grandson could be “high-strung” and “kind of a loner”.

He attributed it to “normal issues for kids these days,” but T.J. Franks Jr, Roley’s former roommate, knew something was off.

“Towards the end, he started acting a little weird, and I don’t know why. But we just explained to him that we needed our own space,” he told The Associated Press.