ST. PETERSBURG — Police shot and killed an ax-wielding man who was chasing people Monday evening around a downtown city block.

The man's alarming pursuit ended about 6:45 p.m. when he encountered an officer across from the open-air post office.

"The first thing the officer saw was a group coming around the corner, in a panic," said police spokesman Mike Puetz. "Then a guy with an ax."

Police and witnesses said the man ignored the officer's orders to drop the weapon, a fireman's ax featuring a long, yellow handle and a red blade. The man kept charging and appeared to be ready to swing at the officer, witnesses said.

"He got within approximately 7 feet and the officer discharged his weapon multiple times," Puetz said.

Paramedics pronounced the man dead at the scene. Police said they believe the dead man was a 27-year-old transient, but did not release his name Monday night.

"We believe he may have had some mental issues in the past," Puetz said.

The man's covered body was on the sidewalk on the east side of Fourth Street, between Central Avenue and First Avenue N next to the city municipal services building, as detectives investigated.

One of the building's first-floor windows was broken, pierced by the officer's bullet. Puetz said a second officer was initially called to the scene but did not discharge his weapon.

Neither officer was immediately identified. As is standard procedure, the officer who fired will be taken off the streets as simultaneous criminal, internal affairs and state prosecution investigations take place.

"They gave him a warning," said Ashton Stottler, 33. "I heard them say 'raise your hands' and 'drop that.' "

Stottler, who was hovering near the city building shortly after the shooting, said he was one of the people chased by the man. He said he sometimes hangs out downtown, but he did not recognize the ax-wielding man.

"We were just passing through," he said. "Walking down the street. And then he just pulled out an ax and started chasing us down the street. He chased us from Williams Park to around the corner."

This is the third time this month St. Petersburg police officers have shot and killed a person, and the sixth time this year. On Sept. 7, officers shot and killed a man on his front porch after he leveled a gun at officers. Five days earlier, they'd shot and killed a different man on his front porch after they said he threatened his neighbor and pointed a gun at an officer. Those shooting are still under investigation.

As cruisers descended downtown Monday night, Williams Park — known as a magnet for the city's homeless, emptied. Less than an hour later, the usually sizable transient population scattered as the rain fell harder.

Those who lingered passed on tidbits of information to gawkers who wandered over from office buildings and bars to snap cellphone pictures.

Mike Smith, 42, said he lives downtown and wanted to see what the commotion was about.

"I heard the man's bicycle was stolen earlier, and he came back with an ax," Smith said. "That's what the streets said."

Police said they could not confirm that. Puetz said detectives did get information that someone saw the man earlier in the day with the ax. It was not immediately clear if anyone called the police at that time.

Smith huddled under a large umbrella and watched the officers work for a while.

"Wow," he murmured. "That's major. But if the cops say put it down … you're supposed to put it down."

Kameel Stanley can be reached at kstanley@tampabay.com or (727) 893-8643.