ALHAMBRA (CBSLA) – An off-duty Los Angeles County sheriff’s deputy was in critical condition Monday night after being shot in the head in a restaurant in Alhambra.

The shooting occurred inside a Jack in the Box near Fremont Avenue and Valley Boulevard.

READ MORE: Braves Take World Series Game 1, 6-2

The deputy was transported to County + USC Medical Center with a head injury and was in critical condition as of Monday night.

In a press conference at 10p.m. Monday night, sheriff’s officials said the deputy was shot in the head while off-duty and wearing civilian clothing.

The 13-year-veteran was said to be ordering food when the suspect walked up to him and shot him once in the back of the head.

The sheriff’s department released photos of the suspect, who was caught on camera shooting the deputy.

California Highway Patrol put out an alert for a white 2006 Kia Sportage with paper plates that was seen on surveillance footage fleeing the scene.

CBSLA’s Chris Holmstrom spoke to a Jack in the Box Employee who was working when the shooting occurred.

READ MORE: Lakers down Spurs, 125-121 in Overtime

“I was actually sitting down in the break room when all I heard was a loud bang,” said Jesus Guzman.

Guzman thought the sound was coming from the kitchen, but then he saw customers running out of the store, and a gunshot victim on the ground.

“I go lean over and I see, I think he got shot in the head because there was a hole in his head,” recalled Guzman.

He then called 911 and told them the man who was shot was not breathing.

Guzman said the suspect fled as if nothing happened.

The suspect was still at large as of Monday night. He was described as a white man 20 to 30 years old, between 5-foot-9 and 5-foot-11, wearing a burgundy short-sleeved button-down shirt, slim blue jeans, a light fedora hat, and sunglasses. His vehicle was described as a white, 4-door, 2010-2014 Kia Sorento SUV with paper plates.

MORE NEWS: Criminal Charges 'Not Ruled Out' After Accidental Prop-Gun Shooting Death Of Halyna Hutchins By Alec Baldwin

Investigators say the suspect is believed to have changed into a black T-shirt and black jeans shortly after the shooting.