MADISON, Wis. — A 19-year-old black man died Friday night after being shot by an officer in Madison, authorities said.

The man was shot after an altercation with the officer and died at a hospital, Police Chief Mike Koval said. He did not know if the man was armed, but said the “initial findings at the scene did not reflect a gun or anything of that nature that would have been used by the subject.”

Authorities have not released the 19-year-old’s name, but family members identified him to local media as Tony Robinson.

The officer’s name and race has not been released. The state Department of Justice’s Division of Criminal Investigation is investigating the shooting.

A crowd of people gathered at the scene Friday night and chanted “Black Lives Matter,” the Wisconsin State Journal reported. Andrea Irwin, who told WKOW that she was Robinson’s mother, said: “My son has never been a violent person. And to die in such a violent, violent way, it baffles me.”

Koval said police were called about 6:30 p.m. Friday because the man was jumping into traffic. A second call to police said the man was “responsible for a battery,” Koval said.

The officer went to an apartment where he thought the man had gone, and forced his way inside after hearing a disturbance. Koval said the officer was assaulted by the 19-year-old and then fired at him. Koval said he believes there was more than one shot fired.

Madison Mayor Paul Soglin called it “a tragedy beyond description,” the newspaper reported. He also said that because of a state-required outside investigation, Madison police won’t be able to provide many details about the shooting.

“I expect there will be a lot of anger and frustrations, particularly from friends,” Soglin said. “I hope as the pain eases that something constructive will come of this.”

Koval mentioned recent officer-involved shootings across the nation, saying “it’s understandable that the reaction at the scene and of some of our citizens is extremely volatile, emotional and upsetting. … We would urge, obviously, that everyone exercise restraint, calm and allow the Division of Criminal Investigation (DCI) to conduct their affairs.”

Sharon Irwin, who told the newspaper she was Robinson’s grandmother, urged protesters to be peaceful.

“I think you need to rise up but I don’t want violence,” she said.