Ohio police officers in Wisconsin for the Republican National Convention shot and killed a man who was wielding two knives near the event, police said.
Milwaukee Police chief Jeffrey Norman said at a news conference that five police officers from Columbus, Ohio opened fire on the man after he ignored commands to drop the knives and then charged at an unarmed person.
Two knives were recovered from the scene, he added.
Police body camera footage from the incident depicted two officers on bikes noticing the armed man.
They can be heard directing him to drop the two blades whilst approaching on foot. The man could be seen not complying and instead moved closer to another unarmed person.
At this point, the two Ohio officers opened fire.
“Someone’s life was in danger,” Mr Norman said.
“These officers, who were not from this area, took it upon themselves to act and save someone’s life today.”
Thousands of police from numerous jurisdictions are in Milwaukee to provide additional security for the Republican convention, which began on Monday.
However, the shooting fueled anger from locals who questioned why out-of-state officers were in their neighbourhood at all, as the incident happened about a mile or so away from the convention site.
The Columbus Division of Police, as well as the chief of staff for Milwaukee’s mayor and a spokesperson for the convention’s joint command centre, all said there was nothing to suggest the shooting was related to the convention itself.
A cousin and others identified the man killed as 43-year-old Samuel Sharpe.
Milwaukee residents and activists quickly converged on the site of the shooting, many of them expressing outrage about the involvement of a police department in town because of the convention.
About 100 people held a vigil and march without incident on Tuesday night, pausing for a moment of silence at the blood-stained spot where Mr Sharpe was killed.
“They came into our community and shot down our family right here at a public park,” said Linda Sharpe, a cousin of the man who was killed.
“What are you doing in our city, shooting people down?”
Linda Sharpe said her cousin lived in a tent encampment across the street from King Park, where the shooting occurred.
Residents said the encampment was a long-standing feature of the neighbourhood, which is home to several social service clinics and a shelter.
Some said Milwaukee police officers are familiar with many of those living in the tents and might have been able to de-escalate the situation.
David Porter, who said he knew Samuel Sharpe and is also homeless, was angry that officers from outside of Milwaukee were in his neighbourhood.
“If Milwaukee Police Department would have been there, that man would still be alive right now,” Mr Porter said.
Mr Norman said 13 officers who were part of a bicycle patrol from Columbus were within their assigned zone having a meeting when they saw the altercation.
“The officers observed a subject armed with a knife in each hand, engaged in an altercation with another unarmed individual,” Mr Norman said.
They only fired after the armed man ignored multiple commands and moved towards the unarmed man, he added.
“This is a situation where somebody’s life was in immediate danger,” he said.
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