Responding to escalating clashes that loom over the presidential race, Joe Biden on Monday condemned the rioting, looting, and violence that has rippled through some protests across America while describing President Donald Trump as a “toxin” who has “poisoned” the country’s values and made it less safe.

Speaking in Pittsburgh after two deadly shootings around protests and counter-protests bloodied streets in Portland, Ore., and Kenosha, Wis., last week, Biden said Trump would only make the country more volatile and dangerous in a second term.

“This president long ago forfeited any moral leadership in this country. He can’t stop the violence because for years he’s fomented it,” said the Democratic nominee for president. “He may believe mouthing the words law and order makes him strong, but his failure to call on his own supporters to stop acting as an armed militia in this country shows how weak he is. Does anyone believe there will be less violence in America if Donald Trump is reelected?”

Biden also unequivocally blasted the lawlessness that has accompanied some protests against police brutality, which have recently included violent confrontations with self-styled far-right militias that have intervened in Kenosha and Portland.

“I want to make it absolutely clear … rioting is not protesting,” Biden said. “Looting is not protesting. Setting fires is not protesting. None of this is protesting. It’s lawlessness, plain and simple, and those who do it should be prosecuted.”

He later added, “Ask yourself: Do I look like a radical socialist with a soft spot for rioters? Really?”

Hours later at the White House, Trump said “the violence is fueled by dangerous rhetoric from far-left politicians,” lumping in Biden, who ran as a relative moderate, with “the radical left.” But Trump refused to condemn his own supporters who have joined the confrontations, including 17-year-old Kyle Rittenhouse, accused of shooting and killing two demonstrators in Kenosha.

“That was an interesting situation,” Trump said. “He was trying to get away from them, I guess, it looks like. And he fell, and then they very violently attacked him. And it was something that we’re looking at right now and it’s under investigation but, I guess, he was in very big trouble. He would have been — he probably would have been killed, but it’s under, it’s under investigation.”

A Trump supporter was shot and killed Saturday in Portland after the president’s backers, encouraged by Trump on Twitter, confronted protesters with paint balls and pepper spray.

Biden’s speech Monday kicked off a furious week of activity in Pennsylvania as the campaigns emerge from the national conventions and near the final two months. Trump’s daughter-in-law, Lara Trump, was scheduled to campaign in Bucks County on Monday, Vice President Mike Pence has an event in Northeast Pennsylvania on Tuesday, and the president is scheduled to speak in Western Pennsylvania on Thursday.

The state is one of a handful of battlegrounds likely to decide the winner of the presidential race. So are Wisconsin and potentially Minnesota, two states that have been at the epicenter of violent police actions, protests, and destruction.

Though most protests have been peaceful, high-profile violence has risen to become a central issue in the presidential campaign, fueled by the deadly shooting in Portland on Saturday and of two people who protested against police brutality in Kenosha earlier last week. Both incidents, pitting Americans against one another, cast a shadow over an already tense presidential race that both parties see as an existential fight.

No suspect had been named as of late Monday in the Portland shooting, which came as Trump supporters drove a caravan through the city, flying Trump flags from their vehicles and confronting protesters who have clashed with authorities there.

“Paint is a defensive mechanism. Paint is not bullets,” Trump said Monday, after encouraging his supporters to join the confrontation over the weekend.

Trump used the Republican National Convention last week to argue that radical agitators are threatening to overrun the country, pitching himself as an enforcer who would keep the country safe. On Monday, he dismissed Biden’s comments against violence, saying the Democrat had failed to specifically name “antifa,” a loose and informal collection of people on the far left who have been blamed for some of the vandalism and destruction.

Biden criticized rioting and looting at least as early as June, in a speech in Philadelphia. But even some Democrats worry that he has been too slow to respond to the escalating situation. Others have criticized him for not going to Wisconsin since the unrest began there after the police shot a Black man, Jacob Blake, multiple times in the back.

Trump plans to speak in Kenosha on Tuesday, and on Thursday will visit Latrobe, Pa., about an hour outside Pittsburgh, his campaign announced. (Wisconsin’s Democratic governor, Tony Evers, has urged Trump to stay away.)

Biden argued that Trump is the cause, not solution, to the country’s increasingly tense divides. He pointed out that the violence is occurring on the president’s watch, along with widespread death and economic pain from the coronavirus pandemic. “Do you really feel safer under Donald Trump?” Biden asked.

Noting that crime fell while Barack Obama was in the White House, Biden accused Trump of trying to turn attention away from a virus that has killed more than 180,000 Americans, and of rooting for conflict so he can change the subject.

“Donald Trump failed to protect America, so now he’s trying to scare America,” Biden said.

“We need to heal,” Biden added, promising a less divisive presidency. “He’s not been part of the solution thus far, he’s part of the problem.”

Trump for weeks has promised “law and order” and a muscular response to protests that turn violent, while blaming Democratic mayors as not responding forcefully enough. But over the weekend, he egged on supporters who rolled into Portland.

On Twitter, the president called the caravan “GREAT PATRIOTS” and wrote that “the big backlash going on in Portland cannot be unexpected after 95 days of watching and incompetent Mayor admit that he has no idea what he is doing.”

Ahead of Biden’s speech, the Trump campaign accused the former vice president of betraying police and falsely said he had not condemned rioting until recently.

“Joe Biden has turned his back on law enforcement time and time again and has blamed the police for the problems in America. That is not right,” Michael Slupe, the sheriff of Butler County, Pa., told reporters on a Trump campaign conference call.

Slupe said peaceful protest “means quiet, holding up a sign,” and that those now in the streets “are ruining America.”

In Philadelphia on June 2, Biden said “there is no place for violence, no place for looting or destroying property or burning churches or destroying businesses.”

On Sunday, he issued a statement calling the shooting in Portland “unacceptable,” adding, “I condemn violence of every kind by anyone, whether on the left or the right. And I challenge Donald Trump to do the same.”