A killer sniper's body was recovered after he deliberately started a brush fire to bring firefighters to a mountain before shooting two of them dead. 

The unidentified ambush killer was found dead near his gun on Canfield Mountain outside of Coeur d'Alene, Idaho on Sunday evening.

His cellphone signal was used to pinpoint his whereabouts and law enforcement exchanged gunfire with the suspect.

He was later found dead close to his gun, but Kootenai County Sheriff Robert Norris says it's still unclear if the sniper was killed by a cop's bullet - or if he took his own life on realizing there was no way out.  

The sniper's body was pulled away from the scene just as the blaze the sniper started began to spread across Canfield Mountain.  

The fire was first reported at around 1.21pm. Two local firefighters - one from Coeur d'Alene Fire Department and another from Kootenai County Fire & Rescue - were shot and killed while scoping out the scene.

A third was left 'fighting for his life' after being struck and rushed to surgery, but is now described as being in a stable condition. 

Police are now investigating whether the gunman may have made the original call to 911 about the fire on Canfield Mountain in an effort to get firefighters to the scene, with Norris saying he is not ruling out the possibility. 

'This was a total ambush. These firefighters did not have a chance,' Norris said. The identity of the firefighters and shooter has not yet been released. 

Harrowing fire department scanner calls revealed the terror the first responders faced as they arrived on the scene. 

'Send law enforcement right now! There's an active shooter zone,' one firefighter could be heard crying out.

'Everybody's shot up here!' the firefighter continued, noting that two battalion chiefs were 'down' and he was 'pinned.'

He was later heard warning his fellow firefighters, 'Stop. Do not come up here.'

'It's clear to me that this fire was set intentionally to draw us in,' the firefighter claimed.