Authorities in the Los Angeles area are now offering $20,000 for information leading to the arrest of an unidentified gunman accused of opening fire at a victim and later shooting "additional rounds into his head" as the victim was on the phone with 911 dispatchers. 

As of this week, Jason Castillo, the victim, remains in critical condition and is unable to speak following the alleged attacks on Dec. 3 in Lancaster, north of Los Angeles, investigators told KTLA. 

"This heinous and deplorable act will not be tolerated in our City," the Los Angeles County Sheriff Department’s Lancaster Station wrote on Facebook. "Please help us find justice for Jason Castillo." 

Surveillance cameras captured images of the unidentified gunman on Dec. 2, 2021.

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Police say that, around 3 a.m. on Dec. 3, "Jason Castillo was first shot while in his vehicle near the intersection of Challenger Way and Avenue K. 

"Injured, Mr. Castillo was able to make his way to the Shell Gas Station and dialed 911," the Lancaster station continued. "As Mr. Castillo laid on the ground, on the phone with a 911 operator, the suspect drove around, approached Mr. Castillo and shot him point blank in the head." 

Det. James Phillips of the Los Angeles County Sheriff’s Department told KLTA that "we definitely believe, with the evidence we have, that during the [first] shooting, they had actually crashed into each other. We are guessing that the suspect was ramming into the victim’s vehicle." 

The car the suspect was last seen traveling in. (Los Angeles County Sheriff's Department Lancaster Station)

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In the second shooting, the suspect was "driving around looking for the victim" and then "approached Mr. Castillo as he laid there and shot additional rounds into his head" during the 911 call, Phillips added. 

Police described the suspect as an adult Hispanic male last seen wearing a green shirt, a black hat and black shorts, who was driving a white, 4-door BMW with tinted windows.