The Westchester County Police Department released the names Monday of its officers who were involved in the deadly shooting of a black Mount Vernon cop.

The officers allegedly fired nine shots, with four to five of them striking Officer Christopher Ridley Friday in White Plains. Authorities said Ridley was holding a gun at a man, Anthony Jacobs. A witness said Ridley, who was in plain clothes, did not follow instructions to drop his weapon.

The county officers include 35-year-old Jose Calero, 28-year-old Christian Gutierrez, 38-year-old Frank Oliveri and Detective Robin Martin, 47. They are on desk duty, but have not yet returned to work.

The men have 27 years combined experience. Gutierrez joined the county force seven months ago and is a former Peekskill officer and Marine. Calero was hired a few months before Gutierrez. Both men are Hispanic. Oliveri, who is white, spent two years with the NYPD before being hired in Westchester six years ago. Martin, who is black, recently marked his 20th year with the force.

At a news conference Monday, Westchester County Police Commissioner Thomas Belfiore said, "The officers involved are understandably and terribly grief-stricken and they and their families are trying to cope the best that they can."

Authorities said the officers later learned that Ridley was an officer and that he had gone back into the nearby county building for help before the shooting. Ridley was allegedly trying to stop Jacobs from assaulting another person.

White Plains police maintain they are conducting a fair and thorough investigation into the shooting. County police are not involved in the probe to avoid a conflict of interest.

The White Plains Police Department encourages any witnesses to come forward. So far, they have interviewed more than 35 people. They are also reviewing the medical examiner's report, looking at a full ballistics analysis and are viewing scene surveillance video.

Jacobs, a homeless man, appeared in court Monday on assault and criminal possession of a weapon charges. He was previously convicted of burglary and served five years at Sing Sing.

Meanwhile, Ridley's loved ones spent Monday placing items at a makeshift memorial in his honor. They described him as a young man who died doing what he loved and who was a mentor for black youths."No matter which way you look at it, someone killed him. He's 23. He just started his life," said the victim's mother, Felita Bouche.

Click here for team coverage about the officers involved.Click here for team coverage about Ridley being posthumously promoted to detective.For Belfiore's news conference about the four officers, go to channel 612 on your iO digital cable box and select iO Extra.

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