Hundreds of far-right protesters swarmed downtown Portland on Saturday, many seemingly ready to do battle with the anti-fascist demonstrators who’d gathered to confront them. By the end of the night, at least 13 people were in custody, but the “potentially dangerous and volatile” situation the city’s mayor had warned of seems to have fizzled out when the Proud Boys and other far-right groups reportedly asked police to help them leave the area.

Their quick exit from the stand-off against anti-fascist groups came just a few hours after President Trump signaled he was watching—which was apparently all many on the far-right wanted anyway.

“Go look at President Trump’s Twitter,” Proud Boys protest organizer Joe Biggs told The Oregonian when asked what message the group wanted to convey. “He talked about Portland, said he’s watching antifa. That’s all we wanted. We wanted national attention, and we got it. Mission success.”

In the tweet, Trump said “major consideration” was being given to naming antifa as an “organization of terror.” He added that he was watching the situation in Portland, and that he hoped the mayor could “properly do his job.”

Portland Mayor Ted Wheeler responded to the jab in an interview with CNN, saying the president’s tweet was “not helpful.”

“This is a potentially dangerous and volatile situation, and adding to that noise doesn’t do anything to support or help the efforts that are going on here in Portland.”

Police seized weapons from multiple groups at the rally, including metal poles, shields and bear spray. But by late afternoon, no major bloodshed had been reported, even though some of the far-right leaders had explicitly called for violence in the run-up to the protest. More than 1,000 Portland police officers were on duty for the event, along with representatives of more than two dozen other law enforcement agencies, including the FBI.

At least 13 people were arrested throughout the day, and authorities said there were sporadic altercations. Video showed black-clad demonstrators smashing out windows of a bus that was believed to have transported Proud Boys members. Shortly after 4 p.m., police declared the demonstrations a civil disturbance after crowds blocked off streets.

Portland Police Bureau Lt. Tina Jones said at least one person was taken by ambulance to an area hospital for an injury, though no further details were immediately available.

The Proud Boys had left the demonstration shortly after noon, reportedly asking police to open a bridge that was meant to be closed during the event so they could make their exit.

“The Proud Boys contacted us or contacted the units on the ground saying that they wanted to leave and so we facilitated for them to leave the area,” Multnomah County Sheriff’s Office Sgt. Brandon White told The Oregonian. “It wasn’t planned. It wasn’t orchestrated. We had a request that they would like to leave the area and so we facilitated.”

The Proud Boys later reportedly released a statement vowing to come back to Portland every month unless the mayor “takes charge and removes the scourge of violent domestic terrorists from his city,” referring to anti-fascist groups.

Wheeler hit back in an evening press conference, accusing Biggs and the far-right group of “misusing public taxpayer resources” with their rallies. “More importantly, I hope that [Biggs] understands that in this national environment where we had some mass shootings just a little over a week ago, there is an environment of fear—that is national, it’s not unique to Portland. But at a time when people are expressing hatred, at a time when people are expressing intolerance, when there’s rhetoric that is aimed predominantly at women and people of color and immigrants, it creates a sense of uncertainty and a sense of fear.”

The Proud Boys deciding to come to Portland, he said, “feeds into this sense of fear.”

For the right-wing demonstrators, the protest got off to a rocky start prior to the weekend, with many of the key organizers getting hit with setbacks ahead of the protest. Biggs said he was visited by the FBI last week, and apparently in reaction to that visit, he wrote in a Facebook post ahead of the rally, “I wanna say again to all attending rally in Portland. Tone down rhetoric.” He vanished from social media prior to the Saturday rally.

Additionally, Joey Gibson, leader of the far-right group Patriot Prayer, was arrested on Thursday on outstanding charges stemming from a violent clash in Portland in May.

Gibson, who was released on bail after the arrest, showed up at the Portland rally on Saturday morning in a Make America Great Again hat. “I’m just here for the ride,” he was quoted as telling The Oregonian.