An unarmed 19-year-old black man was fatally shot Friday night by a white police officer in Madison, Wis., touching off protests and chants of “Black lives matter” that continued into Saturday.

The police chief on Saturday called the incident a “perverse perfect storm” of details that for some appeared to fit the national narrative of officer-involved deaths of black men.

“I get that,” Police Chief Mike Koval said during a televised news conference, as he sought to reassure the community while asking for patience during the investigation. “I understand that.”

Anthony Robinson, 19, was killed about 6:30 p.m. as police responded to multiple reports of a disturbance, Koval said. Officers were told a man was jumping in and out of traffic and was suspected of committing battery before he ran into an apartment, he said.

An officer forced his way inside after hearing sounds of a disturbance, where Robinson struck the officer in the head, Koval said. The officer then fired his weapon.

The officer was identified by Koval as Matthew Kenny, 45, a 12-year department veteran. After the shooting, he was placed on paid administrative leave, Koval said.

Robinson’s mother, Andrea Irwin, declined to comment Saturday.

“All we want right now is to find out all the facts,” said Jerome Flowers, a family friend.

The shooting is being investigated by the Wisconsin Department of Justice’s Division of Criminal Investigation, the result of a 2014 state law requiring outside agencies to probe officer-involved deaths.

“We are resolved that the result of that investigation will be one in which the public can have confidence,” Wisconsin Attorney General Brad Schimel said in a brief statement.

But residents were not waiting for an official result. At least 150 people gathered outside the shooting scene Friday to protest. More protests were held Saturday.

Protests have been staged in Madison for months, many of them organized by Young, Gifted and Black, a group created after 18-year-old Michael Brown was fatally shot by police in Ferguson, Mo., in August.

Now they are protesting a tragedy in their city, said group co-founder Brandi Grayson.

“We were a Ferguson waiting to happen,” Grayson said. “The murder of Tony Robinson is the direct result of racism.”

Grayson’s group and the police chief have angrily clashed this year, adding tension to the current situation.

Protesters and police had appeared to be getting along, with demonstrators repeatedly acknowledging efforts by authorities to accommodate their actions. But the relationship soured in January, when the protest group penned an open letter to Koval, accusing the department of targeting blacks and demanding the release of black prisoners to address “structural racism and bias.”

Police are “what we consider an occupying force in our neighborhoods,” the group wrote, adding, “The relationship that we desire to have with the police is simple: no interaction.”

The letter drew an angry rebuke from Koval.

“I will not buy into the naive supposition that our community’s disparity issues are largely owing to a pervasive pattern of systemic racism by MPD. In fact, I’m fed up with my Department being blamed for everything from male pattern baldness to global warming,” Koval wrote on his official police chief’s blog. “It is time for Young, Gifted, and Black to look a lot deeper at the issues besetting our people of color and stop pandering to the ‘blame game’ of throwing my Department to the wolves.”