PORTLAND, Ore. (AP) — Portland police arrested eight people and fired crowd-control munitions to disperse protesters who threw rocks and bottles during demonstrations in front of law enforcement buildings on Saturday night and Sunday morning.

The series of confrontations began late Saturday, the 30th consecutive day of demonstrations outside the Multnomah County Justice Center, where protesters used fencing and street barricades to block off a street, according to KOIN-TV and the Portland Police Bureau.

Thousands of people in the liberal Pacific Northwest city have turned out every night for a month since the death of George Floyd in Minneapolis. Civil liberties advocates say the police response has been overly aggressive and said in a lawsuit Sunday that the tactics appear designed to squelch free speech.

Portland police said that lasers were shined into officers' eyes, and people threw rocks, bottles and paint at them during the demonstration. After using loudspeakers to tell the protesters to leave, officers used riot-control munitions to disperse the crowd, police said.

It was unclear what munitions specifically were used.

Police said the protesters later reassembled in front a police precinct, and arrests were made when some in the crowd refused to disperse. An officer suffered minor injuries after being struck in the face with a skateboard.

The clashes between police and protesters continued until about 2 a.m. Sunday, with crowd-control munitions also used at a second site where two dumpsters were pulled into the street and several garbage cans lit on fire.

Police were barred under a temporary federal court order from using crowd-control munitions in situations where people engaged in passive resistance could be injured by the devices. That order was extended Friday until July 24.

Much of the protesting has been peaceful. But early Friday a group of several hundred demonstrators set fire to a precinct building while people were inside, the Portland Police Bureau said. In that incident, police used a type of tear gas to disperse the crowd.

A lawsuit filed Sunday by the American Civil Liberties Union alleged police have targeted and attacked journalists and legal observers during their attempt to disperse demonstrations in recent weeks.

The lawsuit filed in federal court includes claims several journalists and two ACLU observers were mistreated, including being beaten by police with batons and attacked with rubber bullets, flash-bang grenades and tear gas.

“The police should not be shutting down the public’s access to the messages and realities of protest in Portland’s streets where people are calling for an end to police killing of Black people,” Kelly Simon, interim legal director of the ACLU of Oregon, said in a statement.

Police did not immediately respond to emails from The Associated Press seeking more information about the latest confrontation and a response to the lawsuit.

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