A 19-year-old Wisconsin man who was shot by a veteran police officer was unarmed, Madison's police chief said Saturday. 

Chief Mike Koval said Officer Matt Kenny, 45, has more than 12 years of experience and was involved in a 2007 shooting but was cleared of any wrongdoing because it was a "suicide by cop-type" situation.

Tony Robinson was shot Friday night after an altercation in which the officer was knocked down by a blow to the head, authorities said. Koval said it wasn't clear whether Robinson, who died at a hospital, was alone in the apartment where the shooting happened, which neighbors said was where Robinson lived.

"He was unarmed. That's going to make this all the more complicated for the investigators, for the public to accept," Koval said.

Several dozen protesters gathered outside the Dane County Public Safety Building on Saturday before starting to walk toward the scene of the shooting, holding signs that read, "Black Lives Matter.” Protesters also shouted the slogan Friday night after the shooting.

Robinson’s grandmother, Sharon Irwin, told The Wisconsin Journal that Robinson was unarmed and asked police, “What happened to your Taser?”

Koval said that more than one shot was fired at the scene.

The state Department of Justice’s Division of Criminal Investigation is investigating the shooting.

The Associated Press contributed to this report

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