By CBSLA Staff

IRWINDALE (CBSLA) – Investigators are looking for a suspect who sucker-punched a 61-year-old grandfather at an Irwindale gas station earlier this month, leaving him with serious brain injuries.

Surveillance video shows 61-year-old Jose Sanchez (left) just prior to getting sucker punched by a suspect at a gas station in Irwindale, Calif., on July 12, 2020. (Irwindale PD)

READ MORE: Los Angeles Clippers Hold Off Lakers, 119-115

The attack occurred at an Arco gas station at 110 Logden Ave. at 1:50 a.m. on July 12, according to Irwindale police.

Surveillance video of the attack shows 61-year-old Jose Sanchez standing outside his pickup truck when the suspect and the suspect gets out of a Honda Pilot and approaches him in the parking lot of the gas station.

They appear to be talking when the suspect suddenly punches Sanchez in the face.

He immediately falls to the ground. Police said he struck his head on the concrete and lays there unconscious as the man leaves. He was taken to a hospital with severe head injuries and brain trauma.

An undated photo of 61-year-old Jose Sanchez. (GoFundMe)

READ MORE: Gaudreau, Tkachuk Lead Flames Over Ducks In Shootout

As of Tuesday, he remains in serious condition at a hospital and Sanchez has no memory of the incident.

Sanchez’s daughter told CBSLA that her father laid on the ground in the parking lot for 20 minutes before being found, losing a lot of blood in the process.

Investigators do not believe Sanchez knew his attacker. There is still no motive in the assault, which at this time is being called an attempted homicide.

Police have since located the suspect’s vehicle, a 2003 gold and tan colored Honda Pilot with license plate number 5VQL448, but the suspect has not been identified.

The suspect was described as Hispanic, in his mid-30s, 6-feet-tall, 275 pounds with a large build, black hair, and a black mustache and goatee. He was wearing a black t-shirt with a Marilyn Monroe design on the front, black and white checkered shorts and gray tennis shoes.

Anyone with information should call detectives at 626-430-2290.

MORE NEWS: La Mirada Home Decorated Like 'National Lampoon's Christmas Vacation' Could Face Fines Over Display

A GoFundMe page has been established to raise money for Sanchez.