In the wake of the deadly ambush on responding firefighters in Coeur d'Alene, Idaho, the suspect's grandfather spoke to ABC News on Monday.

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.

The two slain firefighters, who have not been identified, died on the way to the Kootenai Health campus in Coeur d’Alene, a hospital spokesperson said. One was from the Coeur D’Alene Fire Department, and the other was from Kootenai County Fire and Rescue, authorities said.