CHICAGO (CBS) — A Chicago Fire Department lieutenant died Saturday morning after he was found unresponsive at a South Side firehouse.

Lt. Patrick Hannon, 51, was on duty when he was found in his firehouse quarters Saturday morning. He was given Advanced Life Support and taken to Mercy Medical Center, where he was pronounced dead, according to Fire Media Affairs Dir. Larry Langford.

Hannon was pronounced dead at the hospital at 7:25 a.m. after being found unresponsive at 2534 S. Throop St., the Cook County Medical Examiner’s office said. He died of apparent natural causes.

Hannon worked for Truck 8 in the Bridgeport neighborhood, Langford said. He joined the department in December 1988. He is married and has two children, Langford said. His wife is a Chicago firefighter paramedic.

“Fire Commissioner Robert Hoff and the command staff, as well as rank and file of the Chicago Fire Department, express our sorrow at this loss of one of our own,” Langford said.

(The Sun-Times Media Wire contributed to this report.)

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