(Photo: Twitter/ @JamezeH via Business Insider)

(The Blaze/AP) Demonstrators stormed a police department in Orange County, Calif., on Sunday to protest an officer-involved shooting that left a man dead and led to a violent clash between witnesses and police.

A crowd filled the Anaheim Police headquarters’ lobby Sunday as Chief John Welter prepared to hold a news conference.

Protestors chanted “no justice, no peace“ and ”cops, pigs, murderers” as officers stood by and watched, according to the Orange County Register.

Amateur video, via KCAL, shows the chaos in Anaheim. (Photo via LAist)

It was unclear whether the press conference would go on. Earlier Sgt. Bob Dunn said only credentialed journalists would be admitted “because of security concerns.”

Welter was to address the shooting and confrontation Saturday in which a crowd threw bottles at officers who responded with tear gas and beanbag rounds.

The man was shot in front of an apartment complex around 4 p.m. Saturday following a foot chase, Dunn said. He died three hours later at a hospital.

Watch the disturbing video of subsequent protests, via KCAL:

The New York Daily News relates:

At one point, a police dog gets free of its handler and was seen running through the crowd, past a baby stroller, and biting a man on the arm.

Dunn said the police dog was “deployed accidentally.”

About five hours after the shooting, an Anaheim police helicopter was still hovering above the crowd while officers brandished batons and other weapons in an attempt to restore order.

The deceased man’s niece, 16-year-old Daisy Gonzalez, said her uncle likely ran away from officers when they approached him because of his past experience with law enforcement.

(Photo via LAist)

“He (doesn’t) like cops. He never liked them because all they do is harass and arrest anyone,” Gonzalez told the newspaper after lighting a candle for her uncle. She cursed at officers who were nearby and a police helicopter that hovered overhead.

Crystal Ventura, a 17-year-old who witnessed the shooting, told the Orange County Register that the man had his back to the officer, and was shot in the buttocks area.

The man then went down on his knees, she said, adding that he was struck by another bullet in the head. Ventura said another officer then handcuffed the man, who by then was on the ground and not moving.

“They searched his pockets, and there was a hole in his head, and I saw blood on his face,” Ventura told the newspaper.

“We were all waiting for [Police Chief John Welter] to come and talk to the community and give us an explanation. Why kill this man?” Yesenia Rojas, a 34-year-old woman who lives in the neighborhood, said.