Madison Police Officer Fatally Shoots Unarmed Man

— -- A unarmed black man was shot and killed by a white Madison, Wisconsin, police officer after a struggle inside an apartment, sparking demonstrations after his death.

The state's Department of Justice's Division of Criminal Investigation is investigating the Friday shooting of Tony Robinson, officials said today. Wisconsin law requires an outside agency to investigate officer-involved shootings.

"We all deserve to know the facts in this case," Madison Mayor Paul Soglin said in a statement Saturday. "Tony Robinson's family deserves that, our community deserves that, and the Madison Police deserve that. When the answers come, we will be open and transparent in communicating them."

Robinson, 19, was jumping in and out of traffic on Friday night and allegedly responsible for a recent battery, Madison Police Chief Mike Koval said.

Madison Police Officer Matt Kenny, a 12-year veteran of the department, went to an apartment where he thought Robinson had gone, Koval said. The officer heard a disturbance inside and entered, where an altercation with Robinson began, the police chief said.

Koval said Kenny then shot Robinson, who later died at the hospital.

"Nineteen years old is too young," Koval said at a news conference, adding that Robinson was unarmed.

"He was a great kid. He is a great kid," said Robinson's grandmother, Sharon Irwin. The family was expected to make a statement during a news conference Saturday afternoon.

Kenny, 45, was also injured, said Koval, but his injuries were not disclosed. The officer was placed on administrative leave with pay pending the outcome of the investigation.

Kenny was involved in a police-involved shooting in 2007 and was exonerated of any wrongdoing, said Koval.

After the Robinson's death, demonstrations condemning the shooting began. A crowd gathered where the shooting happened and then left. Some people then headed to the downtown building that houses the Madison Police Department's Central District offices.

"His mother and father, siblings, relatives and friends lost a loved one. His parents are living their worst nightmare," Soglin said. "Our hearts, our thoughts go out to the family and friends who are grieving."

"As a parent, I can only imagine the heartbreak they must be feeling right now in the wake of this tragedy," Wisconsin Attorney General Brad Schimel said in a statement. "Likewise, I am concerned for the officer involved in this incident, who I imagine is experiencing great trauma, as well. They are all in my thoughts and prayers."

Schimel added that the department will conduct a "thorough, professional and transparent investigation."

ABC News' Joshua Hoyos, Corinne Cathcart, Michael DelMoro and The Associated Press contributed to this story.

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