A Northern California sheriff's department has released graphic footage which shows a deputy fatally shooting an armed ex-convict with warrants out for his arrest who opened fire on her at point-blank range.

Napa County Undersheriff Jon Crawford said on Wednesday that the video was captured by the deputy's body camera on Sunday night and appears to show Javier Hernandez Morales, 43, firing at least one shot with a stolen handgun.

The 50-second clip, released by the department, shows deputy Riley Jarecki approaching the driver's side of a red Honda she deemed suspiciously parked near the 1100 block of Henry Road in Napa while patrolling the rural area just before 11pm on Sunday.

The Napa County Sheriff's Office on Wednesday released Deputy Riley Jarecki's body-camera video showing her fatally shooting armed suspect Javier Hernandez Morales (pictured left and right talking to Jarecki Sunday)

The video appears to show Morales, 43, firing at least one shot, but possibly two, at Jarecki at point-blank range

Jarecki asks Morales if she can look around the car, to which he says in Spanish, 'no problem.'

The deputy orders the man not to move, then walks up to the driver's side and tells Morales to roll down the window.

When he does, Morales pulls out a silver revolver and appears to fire at least one, but possibly two shots, at Jarecki and missing.

Jarecki radios in 'shots fired! shots fired!' then retreats to the car's passenger side and returns fire, squeezing off at least 15 rounds and killing Morales, who can be heard screaming in pain inside the car.

The suspect was pronounced dead at the scene. The deputy was not injured.

Jarecki returns fire, squeezing off at least 15 rounds and killing Morales inside the car

Morales, a former farm worker, had an extensive criminal history, which included at least five arrests between 2010 and 2016 (pictured in past mugshots)

Crawford said at a press conference on Wednesday that Morales had several arrest warrants and a loaded .22-caliber rifle in the car. The revolver he used to fire on the deputy was stolen from Fremont.

Morales, a former farm worker from Napa, had an extensive criminal history in the county, which included at least five arrests between 2010 and 2016 on charges ranging from DUI, possession of a concealed, loaded weapon and assaulting a peace officer.

Jarecki has been placed on paid administrative leave pending the outcome of an investigation into the fatal officer-involved shooting that is being carried out by the Napa County Major Crimes Task Force.

Jarecki, a third-generation law-enforcement officer, was sworn in as a Napa County sheriff's deputy last June (pictured receiving her badge)

Crawford praised the deputy for maintaining her composure and fighting for her life in the face of mortal danger, and attributed the fact that Morales' bullets missed her to 'divine intervention.'

'Nobody wants to use lethal force, nobody even wants to use their gun,' he said, 'but she did what she was trained to do to eliminate the threat.'

Jarecki was sworn in as a Napa County sheriff's deputy last June, after previously serving as a cop in Fairfield and Calistoga.

Jarecki is a third-generation law enforcement officer: her grandfather is a retired Napa Police Department captain and her father is Napa County Sheriff's Sergeant Mike Jarecki.