Updated on 2/25/12 at 4:30 p.m.

CHICAGO (STMW/CBS) – A Chicago police officer died Saturday morning after he collapsed while working in the River West area outside downtown.

Officer Preston Ross, 48, was in full uniform, working near the CTA Blue Line station at Grand and Milwaukee avenues Saturday morning when he experienced problems breathing, then collapsed, police News Affairs Officer Robert Perez said.

A Chicago Fire Department ambulance took Ross, a 25-year veteran of the CPD, to Northwestern Memorial Hospital, where he was pronounced dead at about 10 a.m., Perez said. It was determined he suffered a heart attack. A spokesman for the Cook County Medical Examiner’s office said the office was notified of the death of an officer Saturday morning.

Colleagues say  Ross was at work Friday and seemed fine.  They say he was just one year away from retirement and talked about retiring to Las Vegas.

“Preston was a very conscientious police officer. He was very dedicated to his profession,” Chicago Police Capt. Michael Alexander told CBS 2’s Vince Gerasole at the 22nd District in Morgan Park, where Ross was based. “He’s going to be sorely missed. We’re all very shaken up at this particular point in time.”

Just past noon, a police motorcade escorted the officer’s body from Northwestern Memorial to the Stein Institute, where an autopsy will be performed to determine the exact cause and manner of his death.

In a statement, Chicago Police Superintendent Garry F. McCarthy said, “It is with profound sadness that I announce that the Chicago Police Department has lost one of its own this morning, Officer Preston Ross Jr. On behalf of the entire Department, I offer my sincere condolences to Officer Ross’ family, friends and colleagues. We will keep them in our thoughts and prayers during this difficult time.”

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