The Hudson Valley is mourning the sudden death of a longtime local police officer.

On Wednesday, Putnam County Sheriff’s Office Senior Investigator Mark R. Gilmore died at the age of 54.

Gilmore was off-duty and working out at a gym in Dutchess County Wednesday evening when he collapsed from an apparent heart attack, officials say.

He was rushed by ambulance to Vassar Brothers Medical Center in Poughkeepsie, where efforts by the medical staff to revive him were unsuccessful. An official cause of death has not yet been announced.

Gilmore worked for the Putnam County Sheriff’s Office for his entire career, 28 years. He served as a correction officer, deputy sheriff, sergeant and most recently as the senior investigator in charge of the Narcotics Enforcement Unit. He was a member of the Emergency Response Team and was a motorcycle officer. He was also the recipient of several Letters of Commendation and Unit Citations during his career, according to the Putnam County Sheriff’s Office.

“Mark was a consummate professional,” Putnam County Sheriff Donald Smith stated. “As head of the Narcotics Unit, Mark worked hard every day at trying to keep dangerous drugs away from our most precious resources—our children and young adults.”

Gilmore, an Army veteran, is survived by his wife Amy, daughter Mattingly, his father and step-mother John B. and Eve Gilmore, brother J.R. Gilmore and more.

Our thoughts and prays are with Gilmore’s family and friends.

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