CHICAGO - A 19-year-old unarmed African American was killed by a police officer in Madison, Wisconsin on Friday evening, sparking protests.

According to police, the teenager, identified by local media as Tony Robison, was shot dead during a confrontation with the officer who was responding to reports of a man walking in traffic and hitting pedestrians.

The officer followed the suspect to a residence and shot the latter when he was attacked.

Shortly after the incident, more than 100 protesters gathered at the scene.

Madison Police Chief Mike Koval said the Division of Criminal Investigation will launch a probe into the shooting. Under Wisconsin law, police officer-involved shootings are investigated by an outside agency.

Koval acknowledged the anger of the protestors, and urged everyone to exercise restraint.

The shooting took place after a string of police violence against minorities across the country, reminding people of the deaths of black men in Ferguson, Missouri, and Staten Island, New York. Grand juries decided not to indict the police officers involved in those cases.