Police on Sunday said 74 people were arrested for allegedly failing to disperse after Saturday’s “No Kings” demonstration in downtown Los Angeles turned violent, with some protesters throwing chunks of concrete at federal officers and one spray-painting a death threat near the Metropolitan Detention Center.

The arrests included 66 adults and eight juveniles, the Los Angeles Police Department said.

Additionally, one person was arrested on suspicion of possessing a dirk or dagger, police said.

Federal officials told CBS2 that at least two officers were hit by concrete chunks and required medical care.

Andre Andrews Jr., a Navy veteran and independent journalist, had walked the entire route of the Los Angeles rally and captured video of the event. He said after authorities gave the dispersal order, they deployed tear-gas canisters when protesters didn’t comply.

Some protesters wearing shields and gas masks on the other side of a fence at the federal complex picked up the canisters and tossed them back at police. Andrews said some people also smashed concrete barriers into smaller pieces and threw them at authorities.

“Does it make L.A. look bad? No. They’re bad actors causing problems, for sure,” Andrews said. “The peaceful protest was good for the cause. You have the right to do that. But the other people, they were definitely causing problems.”

Those detained included a woman dressed as the Statue of Liberty, smiling as she chatted with an officer who led her away.

The downtown rally began around 2 p.m. Saturday at Gloria Molina Grand Park across from City Hall, followed by a march at 3 p.m., part of a nationwide day of protests against the Trump administration. The downtown protest included tens of thousands of people and was peaceful until the late afternoon.

The LAPD’s incident commander declared a citywide tactical alert around 5:10 p.m. Saturday after a group of demonstrators started kicking a fence in front of the federal detention center at Alameda and Temple streets. Demonstrators were ordered to leave the area.

“Protestors on Alameda between Aliso and Temple have been warned multiple times by federal authorities to not attempt to tear down the gate and not throw items,” according to a post on an LAPD social media account. “Federal authorities are using non-lethal measures to move crowd back.”

Bill Essayli, the first assistant U.S. Attorney for the Central District of California, which includes Los Angeles County, wrote on social media, “To those who were smashing concrete blocks and throwing them at our officers, we have you on video. We will find you and arrest you too. You’ve been warned.”

Earlier, Essayli had written, “My office has authorized immediate arrests for anyone assaulting law enforcement. You will be arrested and charged with a federal felony.”

Video from the scene showed LAPD officers on foot and horseback lining up to push protesters away from the location. Photos showed tear gas in use.

At around 7:25 p.m., the department posted on social media, “multiple arrests being made.” The tactical alert was canceled at 8:03 p.m. A tactical alert allows the department to keep officers on duty past the end of their scheduled shifts.

Obscene graffiti criticizing Immigration and Customs Enforcement was painted on walls near the Metropolitan Detention Center, including “Kill Your Local ICE Agent.”

Essayli posted a video showing a masked demonstrator spray-painting the phrase. “This is a federal crime,” he wrote. “If anyone knows who this person is, please let us know. The @DHSgov tip line is 866-347-2423.”

Los Angeles Mayor Karen Bass and the LAPD had urged participants to keep the demonstrations peaceful and lawful.

“Peaceful protest is our constitutional right,” Bass wrote on social media. “When people come together to make their voices heard, that is democracy in action. Please stay safe and look out for one another.”

In anticipation of the crowds, Caltrans crews Friday placed security gates along on- and off-ramps to the 101 Freeway in the downtown area. During previous No Kings protests in downtown LA, some participants moved onto freeway lanes, temporarily blocking traffic. Streets were blocked in the Civic Center area Saturday, including sections of Broadway and Spring Street.

At least 40 demonstrations were held Saturday in Los Angeles County, including Burbank, Culver City, Hollywood, Long Beach, Malibu, Venice, Woodland Hills and outside Trump National Golf Club in Rancho Palos Verdes.

The Associated Press contributed to this report.