D.C. police lined streets around the White House on Tuesday, periodically clearing out tents, barricades and other structures built by protesters seeking to create an autonomous zone in the area that has been at the center of weeks of protests against police brutality.

The action came after President Trump tweeted early Tuesday that protesters would be met with “serious force” if they tried to establish an autonomous zone and that federal officials would seek long sentences against anyone who toppled statues or vandalized monuments.

The comments followed a day of chaotic demonstrations Monday during which protesters unsuccessfully tried to topple a statue of President Andrew Jackson in Lafayette Square and tried to cordon off a section of a street near the White House before police removed them.

Late into Tuesday night, protesters were fanned across the city from highways to Capitol Hill to the White House.

A group of marchers led by a six-man drum line set out from Black Lives Matter Plaza near the White House, eventually wending its way onto the Ninth Street Expressway and Interstate 395 South. The sound of the drums echoed off a tiled tunnel at one point as police followed in cruisers with lights flashing. The group bounced and danced its way up the highway.

“We’re going to go south, okay? Stay close, y’all,” called a protester. “No one is getting arrested today. Absolutely no one. We’re going to link arms and spread out across the highway.”

Eventually, the drums went silent. Marchers lay down on I-395 for eight minutes and 46 seconds — symbolically marking the length of time that a police officer in Minneapolis knelt on George Floyd’s neck — casting long shadows on the hot pavement. Some people got out of their cars, stopped on a bridge, to take photos or just lean on their arms, looking down at the people on the highway.  

Just before 11:30 p.m., back near the White House, a separate group of young men carried a ladder to the traffic light and covered the “Black Lives Matter” sign with black spray paint. They hung an American flag on the pole and set the flag on fire. The crowd cheered and cursed nearby police.

Other protesters gathered on Capitol Hill’s Lincoln Park, home to another controversial statue. Protesters decried the Emancipation Memorial, which depicts a freed slave kneeling at the feet of President Abraham Lincoln.

Earlier in the day, Del. Eleanor Holmes Norton (D-D.C.) introduced a bill to have the statue removed, saying it did not reflect the efforts African Americans made to free themselves from slavery.

Laurie Solnik was one of several people who visited Lincoln Park to take a picture of the memorial in case it is toppled.

“And you know what? I won’t miss it,” said Solnik, 67, a retired federal employee. “It creeped me out the first time I saw it 28 years ago. Clearly, the subservience versus the dominance — it’s the first thing that hits you.”

Near the White House on Tuesday night, a crowd of several dozen at one point faced off against a line of about 30 D.C. police officers. The scene was mostly peaceful, but anger flared at Mayor Muriel E. Bowser (D), whose administration had ordered the area cleared Tuesday.

Standing on the yellow block letters that spelled “BLACK LIVES MATTER,” a young woman on a bicycle shouted, “Mayor Bowser is a fraud!” Another responded, “She painted this for the white liberals!” 

Protesters had created what they are calling the “BHAZ,” or Black House Autonomous Zone, by setting up barricades and pitching tents in an area near Black Lives Matter Plaza and H Street NW, essentially trying to create an island separate from the city around it. Police dismantled the encampment Monday, but protesters reestablished it overnight into Tuesday.

But throughout Tuesday, police continued to remove tents and structures in the area to keep roads open. D.C. Police Chief Peter Newsham said in an interview that police would not let protesters set up an encampment in the area but would not impede peaceful protests. City officials said it was a hazard to allow tents to be pitched on open roads. They said their actions were not related to Trump’s tweets.

But by early Wednesday morning — almost as soon as police pulled back their line — protesters appeared to try again to re-create the zone.Using electric scooters, plywood from boarded-up windows, debris and a giant coil of rubberized material used on escalator handgrips, they tried to block off their zone. At about 1:45 a.m., police on bicycles moved in. When they went to arrest a woman near 16th and K streets NW, several protesters intervened. Another was taken into custody. Police then fired stun grenades and some sort of smoke to clear the intersection.

In a sign of increased security efforts, workers earlier Tuesday began reinstalling a seven-foot-high, black metal fence along the H Street edge of Lafayette Square. The fence was initially erected in the opening days of protests to keep demonstrators away from the White House, then was taken down. Crews were also installing fencing around St. John’s Episcopal Church near the White House late Tuesday night.

Attempts to create an autonomous zone potentially set up a clash in the same area where federal authorities forcibly removed protesters this month before Trump walked to a photo opportunity outside St. John’s Church, which was damaged by fire during protests over the May 25 killing of Floyd by police in Minneapolis.

“There will never be an ‘Autonomous Zone’ in Washington, D.C., as long as I’m your President,” Trump tweeted Tuesday. “If they try they will be met with serious force!”

Twitter later responded, saying it had placed a public interest notice on the tweet for violating its “policy against abusive behavior.” It said the tweet would remain accessible because of its “relevance to ongoing public conversation.”

In another tweet Tuesday, Trump said anyone who vandalizes or topples a statue could be charged under federal law.

Shortly before departing for events in Arizona, Trump thanked law enforcement for its response Monday night in saving a “great monument,” according to a White House pool report.

On Monday night, protesters looped ropes around a large, bronze statue of Jackson astride a horse in Lafayette Square and tried to pull it down, but U.S. Park Police and D.C. police intervened to stop the action.

Jackson, the seventh president, is known for signing the Indian Removal Act, which led to the forcible relocations of thousands of Native Americans and the deaths of thousands more. Jackson also opposed the abolition of slavery and owned enslaved people.

Dozens of protesters camped in the reconstituted BHAZ nearby on Monday night into Tuesday. The zone seemed to be inspired by the autonomous zone set up by protesters in Seattle’s Capitol Hill neighborhood. That zone has been dubbed the CHAZ.

But the effort in the District was short-lived. D.C. police arrived on the scene Tuesday morning. Shouts began to carry down H Street NW just after 10 a.m., stirring demonstrators who had spent the night nearby.

“Riot gear!” demonstrators called. “Riot gear! Get up! Get up!”

A handful of bleary-eyed volunteers who had been operating street medic tents outside St. John’s Church scrambled to their feet. They grabbed what they could carry as police approached, marching toward them, batons and bicycles extended.

“Move,” the D.C. police officers shouted in unison.

Eric Otani, 30, who said he had been helping pull injured demonstrators out of crowds and over to medic stations almost daily since the protests began in the past month, was among about 10 people pushed back from the church as police moved in.

He said they tried to tell the officers that they had permission to be on church grounds “for humanitarian purposes,” but the officers didn’t respond.

By 11:30 a.m., more than 100 police officers lined 16th Street NW, standing on the yellow Black Lives Matter sign painted on the street as demonstrators’ tents and supplies were hauled away in city garbage trucks.

Trump’s ultimatums to protesters angered some and prompted expressions of concern from members of the D.C. government.

Elizabeth Tsehai, an immigrant from Ethiopia, gained attention three weeks ago when she was hauled out of her BMW by federal officers during protests in front of the White House. She returned Tuesday after protesters called for reinforcements on social media.

She said she saw Trump’s desire to crack down on protesters as a dangerous step closer to authoritarianism.

“I grew up during a time of turmoil in Ethiopia,” she said. “But this is supposed to be a democracy. Lafayette Square is hallowed ground. People have been protesting there since the beginning of this country. For them to be forcibly clearing the square for no other reason than to placate Trump is ridiculous.”

D.C. Council member David Grosso (I-At Large), one of the furthest-left members of the council, called on the city and D.C. police to shield the demonstrators trying to form an autonomous zone rather than clearing them out. He said the city should “give them the space to have a voice.”

A U.S. Park Police spokeswoman said Tuesday that Park Police officers had made two arrests as they cleared protesters during the effort Monday to topple the Jackson statue. D.C. police, who also were involved, confirmed that two arrests were made Monday afternoon, but it was unclear whether those were the same two arrests Park Police reported.

Newsham, the D.C. police chief, said protesters “cannot set up tents or grills in the middle of our streets. We’re going to keep our streets clear and try to communicate to people involved in that behavior to move.” But he said his officers would “facilitate peaceful demonstrations,” which stretched throughout the day.

Daniel Walls, of Northeast Washington, cradled his sleeping 2-year-old daughter on his shoulder as he walked along Black Lives Matter Plaza on Tuesday evening. His wife and two other children walked with him, listening to drummers and taking in the protest.

“I came here because I’m an American and I believe that America stands for freedom and equality for all people,” said Walls, 53. “I’m here to voice my opinion and to show my children that through unity we can make change.”

Julie Zauzmer, Dana Hedgpeth, John Wagner, Ann E. Marimow, Fenit Nirappil, Paul Duggan, Perry Stein, Fredrick Kunkle, Rachel Chason, Rebecca Tan and Peter Hermann contributed to this report.