Two Los Angeles County Sheriff Deputies, a man, and a woman are 'fighting for their lives' after a lone gunman shot them in the head in an ambush.

The incident happened at the Metro Blue Line station at Willowbrook Avenue and Compton Boulevard. The location is just a short distance from the Compton sheriff's station.

Surveillance footage of the shooting shows the suspect ambush the deputies as they sat in the patrol car.

Warning: Footage Contains Graphic Images

A man dressed in dark clothing walks up to the parked police patrol cat at the Metro station.

He then approaches the window on the passenger's side and fires several times at a close range.

The assailant then runs off from the scene on foot.

Shortly, one deputy emerges from the passenger side and stumbles around on foot for several seconds before the footage ends.

While the deputies sustained fatal gunshot wounds in the head, they underwent surgery at a local hospital.

However, according to police reports, they're in critical condition.

The department tweeted:

"Moments ago, 2 of our Sheriff Deputies were shot in Compton and were transported to a local hospital."

"They are both still fighting for their lives, so please keep them in your thoughts and prayers."

In a later tweet, the department said:

"We stand with our brothers and sisters at the @LASDHQ.

"The thoughts and prayers of the men and women of the LAPD, are with the two deputies that were ambushed while sitting in their vehicle."

Both deputies were sworn in 14 months ago. The female deputy is a 31-year-old mom of a 6-year-old boy while the man is 24.

Sheriff Alex Villanueva said:

"That was a cowardly act."

"The two deputies were doing their job, minding their own business, watching out for the safety of people on the train."

"To see somebody just walk up and start shooting on them. It pisses me off. It dismays me at the same time. There's no pretty way to say it."

Officials Weren't Able to Get a Detailed Description of the Shooter

Following the incident, a group of anti-police protesters showed up at the hospital where the deputies were admitted.

However, cops soon dispersed them after some tense moments with the officers guarding the entrance.

Witnesses say members in the group were chanting anti-law enforcement slogans. And at one point, they also tried to get inside the hospital.