Just after daybreak, Lt. John Sharpe lowered the American flags outside Engine Co. 38 to half-staff, but even as night fell he was still struggling with why.

Retired city firefighter Mark Barry had been shot to death late Sunday while walking his dog a few blocks from his home in Marshall-Shadeland, and the news had started to swirl around the fire station where he used to work.

"I was shocked," Lt. Sharpe said. "It was a blow to the stomach. Worse than that ... I said, 'We need to lower the flag.' "

It was the least he could do for the engine driver who had become a mentor and a friend while fighting countless fires on the North Side. Mr. Barry, 55, retired in 2005 after 27 years with the Fire Bureau.

"Nobody knew the rig better than 'Marko' Barry," Lt. Sharpe said. "If you had a fire and you were with Marko, you were in good shape."

Police also sought answers in his death Monday. Officers arrived at Mullins Street and Woodland Avenue just after 10 p.m. to find him lying in the street, guarded by his dog. He had been shot in the chest, and paramedics pronounced him dead at the scene.

Police could provide no information about possible suspects or motive.

Mr. Barry's relatives gathered Monday at his home on nearby Plough Street, about a block from the shooting scene, but they declined to comment.

As a pump man, Mr. Barry drove the engine full of firefighters to and from scenes, maneuvering it on narrow streets and operating its pump.

"It's a big, big responsibility, and he did very well with it," Lt. Sharpe said. The two met when the lieutenant was fresh out of training. Mr. Barry "took a rookie under his wing" and they grew close, though the two worked different shifts.

Even after his retirement, Mr. Barry would stop by the station to catch up and meet the new recruits.

Lt. Sharpe called Mr. Barry last week, and he seemed in his usual good spirits. A former U.S. Marine, he loved his job, his dog, and his black Harley-Davidson.

He worked at Sam's Club on Mount Nebo Road in the North Hills.

The company said Mr. Barry was "a valued member of our Sam's Club family who was well-liked and respected by those who knew him."

Funeral arrangements are being handled by O'Brien Funeral Home, North Side.

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