St. Louis city police officers shot and killed a man they say brandished a knife at them outside a market Tuesday afternoon. The shooting was about 12:30 p.m., police said.

Witnesses said the man who was shot had been inside Six Stars Market at Riverview Boulevard near McLaran Avenue. He took items from the market and left, followed by a market employee, witnesses told the St. Louis Post-Dispatch .

When the market employee told the man he would have to pay for the items, the man started throwing the items on the street and sidewalk. St. Louis Alderman Dionne Flowers, who works at a nearby beauty shop, witnessed the encounter, according to St. Louis Police Chief Sam Dotson. She described the man as acting erratically and grabbing at his waistband, Dotson said.

"The store owner and the alderwoman said the suspect was armed with a knife, acting erratically, pacing back and forth in the street, talking to himself," said Dotson, who spoke at the scene.

Employees at the market and the beauty shop called 911 and two police officers arrived, police said.

The officers ordered the man to get down, according to Dotson. The man, 23, became more agitated and walked toward them, reaching for his waistband. Witnesses told police the man was yelling, "Shoot me, kill me now!" during the encounter.

The officers drew their weapons and ordered the man to stop. He did stop, but then pulled out a knife and came at the officers with it held up high, Dotson said. They ordered him to stop and drop the knife. When he got within two or three feet of the officers, they fired, killing the man.

A crowd of about 150 gathered at the scene of the shooting in the moments after the incident, many of whom expressed anger that cops had not used other means of restraint, ABC news reports.

"You don’t need to shoot if you’ve got a Taser and he's got a knife," one bystander said.

"You just kill, kill, kill because you got a gun," another said. "They could've tased him. He was by himself."

"They’re trying to shoot us down," a third onlooker said.

Many in the crowd began chanting "Hands up, don't shoot," and "No justice, no peace," the chants that have been a hallmark of the protests in Ferguson over the past 10 days.