Protests are erupting in Madison, Wisconsin, following the fatal shooting an African-American teenager by a police officer Friday night.

Officials say the incident occurred around 6:30 p.m. Friday evening after a police officer got into a confrontation with a 19-year-old, who was reportedly jumping in and out of traffic.

"The same subject had been responsible for a battery that had recently been committed," Madison Police Chief Mike Koval said.

The officer, who was called to investigate the man for jumping into traffic, followed the man to the residence where the battery allegedly took place. That's where the officer says he was attacked and he shot the victim in self-defense, said Koval, the Wisconsin State Journal reported.

The teenager "assaulted my officer and in the context of mutual combat, the officer did draw his revolver and subsequently shot the subject," Koval said. "The initial finds at the scene did not reflect a gun or anything of that nature."

Although police have yet to identify the teen, a family spokesman has come forward saying the deceased was named Tony Terrell Robinson Jr., a graduate of Sun Prairie High School.

Following the shooting, protesters held a sit-in at Madison City Hall. A large crowd also gathered at the scene carrying signs and chanting "black lives matter."

"In light of so much things that have happened not just across the country, but in our own community, it's understandable that the reaction at the scene and of some of our citizens is extremely volatile, emotional and upsetting. And we understand that," Koval said at a news briefing Saturday.

However, Chief Koval also called for restraint and noted that an outside agency will investigate the incident.

"That's absolutely appropriate under these circumstances. We would urge, obviously, that everyone exercise restraint, calm and allow the Division of Criminal Investigation to conduct their affairs," he said.

During an interview with WKOW-TV, the mother of the victim, Andrea Irwin, said "My son has never been a violent person. And to die in such a violent, violent way, it baffles me."