MADISON, Wis. -- A Wisconsin prosecutor cleared police officers from Ohio of any criminal liability Monday in a fatal shooting last summer near the Republican National Convention.

Officers from Columbus, Ohio, were among thousands of officers from multiple jurisdictions providing extra security for the July convention in Milwaukee.

According to a letter Milwaukee County District Attorney Kent Lovern sent to Columbus Division of Police Chief Elane Bryant on Monday, a group of 14 Columbus officers had gathered in a park near the convention arena for a briefing on July 16 when they saw 43-year-old Samuel Sharpe approaching another man with a knife in each hand. The officers opened fire after Sharpe refused to drop his knives and lunged at the man.

Thousands of officers from multiple jurisdictions were in Milwaukee to provide additional security for the convention. The shooting was not connected to the convention in any way, but people in the neighborhoods around the park questioned how out-of-state police could justify killing a Wisconsin resident.

Lovern wrote in the letter that Wisconsin law allows someone to use deadly force to protect someone else if that person believes it’s necessary to prevent imminent death or great bodily harm. The five officers who fired on Sharpe told investigators they believed Sharpe meant to seriously injure or kill the other man, Lovern wrote.

Officers could be heard on body camera footage before the shooting identifying themselves as police and ordering Sharpe to drop his knives, but Sharpe ignored them and continued toward the man, Lovern said.

A voicemail left with the Columbus Division of Police's public information office seeking comment on Lovern's decision wasn't immediately returned.