BOISE — Two firefighters were fatally shot while responding to a fire in northern Idaho's Canfield Mountain area near Coeur d'Alene, triggering an ongoing manhunt.

Kootenai County Sheriff Bob Norris said the suspect — or suspects — are still firing at first responders using high-powered rifles and are hiding in dense brush. Law enforcement is prepared to neutralize the active threat and has urged the public to avoid the area.

Authorities suspect the fire may have been deliberately set to ambush emergency crews. The shooting began about 40 minutes after firefighters arrived at 1.21pm.

Governor Brad Little condemned the attack as a "heinous assault" and asked Idahoans to pray for the victims and their families.

With the perpetrators still at large and showing no signs of surrender, authorities warn the situation could turn into a prolonged operation.