Wisconsin police admit the 19-year-old teen shot and killed by police in his home Friday evening was unarmed at the time of his death.

"He was unarmed," police chief Mike Koval said of Tony Robinson. "That's going to make this all the more complicated for the investigators, for the public to accept."

According to The Associated Press on Sunday, authorities also concede Officer Matt Kenny was not wearing a body camera when he forced his way into Robinson's apartment after allegedly hearing a disturbance coming from the residence.

Koval added Kenny was injured during his confrontation with Robinson but declined to disclose what the officer's alleged injuries consisted of. Police have also maintained Kenny only fired his weapon after being assaulted by Robinson.

Police were initially called to the neighborhood by reports of a "person jumping into traffic." Reportedly, a second call alleged the man was "responsible for a battery."

On Sunday morning, a balloon-filled memorial lined the street near the home where Robinson was shot and organizers were planning a demonstration for later in the day.

Hours earlier, several demonstrators marched on police headquarters, carrying signs and chanting "Black Lives Matter," a slogan adopted by activists and protesters across the country in the wake of several deadly police shooting involving young, black men.

The shooting came just days after federal officials revealed they had uncovered systematic patterns of abuse from members of the Ferguson, Missouri, police department targeting minorities. The investigation came in the wake of the shooting death of 18-year-old unarmed black teen Michael Brown at the hands of Officer Darren Wilson.

Kenny has been a member of the Madison Department for more than 12 years. Back in 2007, he also shot and killed another suspect but was cleared of any wrongdoing after authorities deemed the encounter a "suicide by cop" situation.