A 37-year-old man faces arson charges and is being held on a $1 million bond for allegedly starting a wildfire that destroyed hundreds of homes near Spokane.

While city officials focus on the aftermath, investigators relied on the account of a local witness who observed the suspect's movements before the fire began.

Paul Child told KIRO 7 that he was one of those witnesses. Child was with his grandchildren Saturday when he spotted a man he would later learn was Aaron Farinacci near railroad tracks near North Old Trails Road.

Child said he noticed the man twice as the individual headed into town last Saturday, the day the Old Trail Fire was started. "My suspicions were up then at that point in time," Child said.

Aaron Farinacci appeared in Spokane County Court on Tuesday following his arrest Monday. He was charged with first-degree arson in connection with the Old Trails Fire.

Child said he saw Farinacci a second time while driving back up a nearby hill. Child described seeing the man bending over in a vegetated area moments before smoke became visible.

"As we are coming back, we came up the hill and that individual was still in that same area," Child said. "Only this time, he was bent over and looked like he was doing something in the grass and tree area." Flames and smoke appeared in the same location shortly after the sighting.

Child said he immediately connected the man to the rising smoke.

"I told myself that SOB started a fire," Child said.

He flagged down arriving fire crews and police to report the individual he had seen. Police took Farinacci into custody for questioning within minutes of Child's report.

When Farinacci was arrested Monday, investigators found a box of matches, a lighter and a pack of cigarettes in his fanny pack.

Child told investigators he was certain of the suspect's identity when officers asked him to confirm it at the scene. "And he faced us, and police asked us if that was him. And 100%. That's the individual we saw five or 10 minutes before this fire had started," Child said.

He told KIRO 7 the experience would stay fresh in his mind for the foreseeable future.

Farinacci will remain in custody on a $1 million bond. Court conditions state that if he posts bond, he is prohibited from possessing any lighters, matches, torches or other fire-starting devices.

Child said he hopes the arrest provides some closure for those who lost their property. "Hopefully he will be held accountable for all the action, and you know the devastation that he's caused to the city," Child said.