(CBS/AP) ANAHEIM, Calif. - Riot police fired bean bag rounds and pepper balls into a crowd of protestors late Tuesday outside City Hall as council members inside voted unanimously to ask the U.S. attorney's office to investigate recent officer-involved shootings, including one of an unarmed man.
About 250 riot police were called in by officials to quell the more than 600 demonstrators before restoring order. Twenty-four people were arrested in the unrest.
The back-to-back weekend shootings have sparked four days of protests. A crowd of protesters who were shut out of the council meeting because there was no more room grew violent, tossing rocks and bottles at police and ignoring warnings to disperse.
Officers formed lines to try to contain the crowd as residents set fire to trash cans, loudly taunted police and swarmed a Starbucks, breaking windows.
Police helicopters hovered from above as colorful fireworks from nearby Disneyland lit up the sky.
CBS station KCAL reports that some of the people in the crowd were trying to hold a peaceful demonstration, but others began chanting, swearing and yelling at police officers.
"We want a peaceful demonstration, but when the cops are pushing us off because they want to show that they have control, then they start hitting us with their batons," one demonstrator told CBS2/KCAL9 reporter Louisa Hodge.
"They hit a woman when we were just standing there voicing our opinion," he said.
The killing of Manuel Diaz and another man on Sunday have taken the tally of shootings by police officers in this Orange County city to six so far this year, up from four a year before. Five of the incidents have been fatal.
Diaz's family on Tuesday filed a civil rights lawsuit seeking $50 million in damages from the city of Anaheim and its police department, claiming he was shot while running away, said lawyer James Rumm.
Mayor Tom Tait said a description from court papers relayed to him by a reporter that Diaz had been shot in the leg and in the back of his head was "unsettling."
Theresa Smith, whose son was killed Dec. 11, 2009, by Anaheim officers at a Walmart store, said she went by the scene of Saturday's shooting and was astounded by what she saw.
"There were pieces of brain on the ... darn grass, in front of all these children, in front of all these people," Smith said. "This traumatizes people, and these people are angry."
The police union issued a statement defending the officers involved in the shootings and said both men killed were gang members who had criminal records.
The union also said that just before Diaz turned toward officers during Saturday's confrontation, he pulled an object from his waistband -- a common place where gang members hide guns.
"I believe that the independent investigations by the Orange County district attorney's office into both incidents will show no wrongdoing by these officers," said Kerry Condon, the police association's president.