Tensions between some protesters and Portland police flared Thursday, ahead of a looming late-night showdown outside a Southeast Portland police precinct for the second straight day.

The city’s mayor and police chief denounced destructive actions by a splinter group of protesters. The group that promotes the nightly gatherings vowed more “direct action” Thursday night near the Portland Police East Precinct.

By 9:30 p.m., more than 200 people had gathered for the night’s protest at a nearby school and park. Messages of support for police covered the boarded-up precinct. A few officers stood on the roof, surveying the crowd that slowly started to gather in front of the building.

The large group of marchers arrived around 9 p.m., chanting the names of people killed by police in Oregon. Police immediately greeted the crowd with a warning issued by a loudspeaker.

”We believe your intention is to vandalize or attempt to burn down East Precinct,” an officer said. “If you attempt to break into or burn East Precinct, you will be subject to arrest or the use of crowd control munitions.”

The crowd of 200 continued to shout the name of police victims. Some people threw paint on the building, a security camera and the plywood surrounding it. Paint splashed on some people, including a woman who appeared to be trying to stop protesters.

Around 9:50 p.m., less than 10 minutes before the crowd arrived, police deemed the gathering unlawful and ordered people to leave. The crowd largely stayed.

Protesters near the front of the group started a fire contained inside a trash can near the brick building. One person painted graffiti on the building. Police repeated the demand for people to leave. Many people stood around as music played in the background.

Police in riot gear arrived at 10:20 p.m. to force people to move away from the precinct. An officer on a loudspeaker told people to walk east or risk the use of force or arrest. As police moved east, officers appeared to slash the tires of a van that provided food and other types of resources to protesters.

Police pressed the crowd east on Stark Street, against traffic blocked in the fray. Officers ran at times toward the crowd to keep people moving. Some of the officers were state troopers, as identified on their uniforms.

Portland police said later on Twitter that some people threw pieces of twisted rebar into the streets, damaging the tires of of at least two police vehicles that drove over them.

The police push stopped at Ventura Park, about a half mile from the precinct. Police blocked protesters from walking back onto Stark Street. Most officers retreated around from 10:35 p.m., boarding vehicles made to transport several officers at once. Some people threw things at the vehicles as they left.

Another police line soon formed about a block east of the park. The police line stretched into a residential yard. Police shouted commands at protesters to keep away. Police set off stun grenades and devices that emitted smoke into the air. Police retreated from that area around 10:45 p.m.

The crowd began to slowly move west, in the same direction of officers. Many people gathered around 108th Avenue, where Stark and Washington streets converge.

At one point, several people gathered in the parking lot of a nearby apartment, where an altercation occurred Wednesday night between a handful of protesters and a woman wearing a Nazi armband.

Police arrived just before 11 p.m. to break up the crowd in the surrounding area, this time pushing people west. Officers again ran and yelled at people. The group was split into at least two factions. Police faced off with some protesters at 102nd Avenue and Pine Street.

After police retreated around 11:10 p.m., protesters wandered through the streets and eventually began to reconverge around 103rd Avenue and Washington Street. Officers also staged nearby.

The demonstrations began 71 days ago after the Minneapolis police killing of George Floyd, and have often led to confrontations between protesters and police.

Those clashes have shifted in recent days to police buildings in different parts of the city. A few hundred have turned out for the gatherings, in comparison to the thousands who have recently joined together downtown.

A handful of people in the recent roving crowds has routinely drawn out police by throwing things, pointing lasers and lighting small fires.

Mayor Ted Wheeler and Portland Police Chief Chuck Lovell pleaded for the destruction to end at a Thursday afternoon press conference. Wheeler called the targeted damage of police precincts a distraction from the Black Lives Matter movement.

Nevertheless, plans circulated early Thursday on social media to meet again near the East Precinct. Pacific Northwest Youth Liberation Front, a group that has called for the roving protests outside police precincts, promoted the event.

Portland police responded on Twitter by saying the “call for direct action will not go unanswered.”

The police tweet sparked immediate and widespread questions and criticism. The American Civil Liberties Union of Oregon said the police rhetoric was escalating tensions.

“Preemptive crackdowns on protests didn’t work at the beginning, and they still don’t work now,” the ACLU said.

Wednesday night’s gathering at East Precinct quickly escalated to a riot declaration after a handful of demonstrators targeted the building’s entrance by ripping off plywood, using tools to crack windows and lighting a fire in a trash can next to the building. Portland police responded with crowd-control munitions and tear gas to break up the crowd. With the help of state troopers, police advanced on the crowd multiple times to keep people from returning.

The Portland Police Bureau East Precinct sits a five-minute walk from a park where protesters have gathered for two nights straight.

The city was sued in June and July over local officers’ use of tear gas, and a federal court order issued in early June temporarily bars Portland police from using the gas unless officers believe someone’s life or safety is in danger.

Wednesday was the first night officers used tear gas to disperse Portland protesters since federal authorities relinquished control of downtown federal courthouse security one week ago.

Confrontations have decreased downtown since state police took over that job. Small crowds still gather there and at other peaceful marches, including one Thursday in Southeast Portland.

Eder Campuzano, Beth Nakamura, Brooke Herbert and Mark Graves of The Oregonian/OregonLive contributed to this report.

— Jim Ryan; jryan@oregonian.com; 503-221-8005; @Jimryan015

— Kale Williams; kwilliams@oregonian.com; 503-294-4048; @sfkale

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