New York State troopers busted an upstate cop for "assassinating" an Old Navy store manager in a Wallkill mall parking lot, authorities said yesterday. Crawford cop Kevin Griffin was brought in for questioning last Friday about the killing of Timothy J. Ruiz, gunned down outside the Galleria Mall in Orange County on March 13, said State Police Troop Commander Major John P. Melville. While at the State Police barracks in Middletown, the 40-year-old Griffin began making "admissions implicating himself in the murder," Melville said.

Cops believe Ruiz, 22, left work around 7 p.m. while Griffin sat in his 2004 Chevrolet Trailblazer with a Marlin .22-caliber bolt-action rifle.

"This was not a random act of violence," added Capt. Wayne Olson of the New York State Police. "We believe Timothy Ruiz was targeted."

Olson wouldn't comment on a report in the Times Herald-Record of Middletown that Griffin believed his girlfriend, an assistant manager at Ruiz's store, was involved with the victim.

But he did confirm "jealousy was part of the motive for what happened."

Griffin, a cop for 18 years, has been on disability leave since being in an accident in his patrol car.

While walking to his car on the day of his murder, Ruiz was picked off by Griffin with one shot to the right side of his chest, Melville said. Ruiz died later that night at the Orange Regional Medical Center, Horton Campus.

The troop commander noted Griffin's gun, which was seized by the State Police, provided ballistic examiners with evidence tying him to the crime.

"Ballistic examinations at the NYSP Forensic Investigation Center . . . have resulted in consistencies being found in the round used to assassinate Mr. Ruiz, and a round previously fired into the Ruiz's residence" in Pine Bush, Melville said.

Griffin, of Ellenville, was charged with second-degree murder, arraigned over the weekend and held without bail at the Orange County Jail. The officer was suspended, "his shield and identification confiscated," Melville said

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