A California man charged with murder in the ambush killing of a Los Angeles County sheriff’s deputy pleaded not guilty by reason of insanity Wednesday in court, the district attorney’s office announced.

Officials say Kevin Cataneo Salazar fatally shot Deputy Ryan Clinkunbroomer, 30. who was sitting in a patrol car, on Saturday. The attack occurred in Palmdale, California, a city of more than 167,000 residents in the high desert of northern Los Angeles County.

Salazar pleaded not guilty to one count of murder plus special circumstance allegations of murder of a peace officer, murder committed by lying in wait, murder committed by firing from a car and personal use of a firearm, according to The Associated Press. He was arraigned at the Michael Antonovich Antelope Valley Courthouse. 

A representative for Salazar did not offer a comment but confirmed the dual plea. Prosecutors haven’t laid out a motive in the case or said whether Clinkunbroomer and Salazar previously knew each other.

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'Intentionally killed the deputy'

Salazar allegedly followed Clinkunbroomer from the Los Angeles County Sheriff’s Palmdale Station to a nearby intersection on the Sierra Highway Saturday just before 6 p.m. Salazar later "intentionally killed the deputy" by “lying-in-wait” and shooting at him before speeding away, according to Los Angeles County Sheriff Robert Luna.

A good Samaritan found the wounded deputy and sought help. Clinkunbroomer was sent to a local hospital where he later died.

Salazar was arrested Monday after an hourslong standoff with sheriff’s deputies. He had barricaded himself inside his family’s Palmdale home.

Salazar remained held without bail and is scheduled to return to court in November. Rosenstock did not immediately respond to a request for additional comment, though his office said the legal team would not be discussing the case further.

At an afternoon news conference, District Attorney George Gascón said prosecutors owe it to the slain deputy’s family to secure a conviction and a sentence of life.

"We’re going to do everything in our power to make sure the defendant never gets out of prison," Gascón said. He was flanked by Clinkunbroomer’s fiancée, parents, brother and sister. Dozens of sheriff’s deputies lined the walls wearing black mourning bands over their badges.

Searching for the suspect

Luna said detectives worked 36 hours to identify and arrest a suspect in the deputy’s killing.

Community tips led authorities to Salazar's Palmdale home, where he was arrested early Monday after a four-hour standoff. He surrendered at about 5 a.m. after deputies forced him out of the residence with a chemical agent.

The suspect's mother Marle Salazar told the Los Angeles Times her son was diagnosed with paranoid schizophrenia about five years ago and twice attempted suicide. She added that deputies had been called to the home when her son refused medication and became aggressive, usually to himself.

If convicted, he faces a sentence of life in prison without parole. A preliminary hearing is scheduled for Nov. 7 in Lancaster, California.

' Best guy I ever met'

Clinkunbroomer was a third-generation member of the department, following in the footsteps of his father and grandfather. He was an eight-year veteran of the force who had worked out of Palmdale for the past five years. About 18 months ago he became a training officer, Luna said. Clinkunbroomer had proposed to his fiancée days before the shooting, Luna said.

Brittany Lindsey, Clinkunbroomer’s fiancée, fought back tears as she recounted their plans to get married and raise a family.

“Ryan was the best guy I ever met,” Lindsey said during the news conference. “I couldn’t wait to start our lives together.”

Contributing: John Bacon, Jorge L. Ortiz, USA TODAY; The Associated Press