Portland police have arrested two people outside the Portland State University campus library, as they move to clear the building, which was occupied by protesters. Police said they encountered "barricades" as they entered the building.

Individuals remaining in the building are under arrest for second-degree trespassing, police announced Thursday. The area surrounding the library has been closed off.

Police also warned that anyone resisting arrest could have force used against them and be subject to more criminal charges.

President Joe Biden addressed the nation on Thursday saying that free speech and the rule of law must both be upheld.

"We are not an authoritarian nation where we silence people or squash dissent, the American people are heard. In fact, peaceful protest is the best tradition of how Americans respond to controversial issues," Biden said, speaking from the White House.

But, he condemned the destruction of property, shutting down campuses and forcing the cancelation of classes and graduation, saying it isn't peaceful protest.

"Dissent is essential to democracy, but dissent must never lead to disorder or to denying the rights of others so students can finish the semester and their college education," Biden said.

Biden last commented on college protests on April 22 -- before there was an escalation of suspension and arrests at campuses across the country -- at the time condemning antisemitic actions and those who don't understand the plight of Palestinians in Gaza, a message he reiterated Thursday.

"There is no place for hate speech or violence of any kind whether it's anti-Semitism, islamophobia or discrimination against Arab Americans or Palestinian Americans. It’s simply wrong. There’s no place for racism in America," Biden said.

President Joe Biden, making his first remarks on the surge in protests on college campuses, said the protests have not pushed him to reconsider his policies in the region.

"Mr. President, have the protests forced you to reconsider our policies?" a reporter asked Biden Thursday.

"No," Biden said, before walking away from the podium.

At least 132 people were arrested on Thursday in protests at UCLA according to California Highway Patrol.

In a letter authorizing the NYPD to enter the Columbia University campus and break up the protest, the school detailed the backstory on its recent talks with those in the encampments and the takeover Tuesday night of Hamilton Hall.

According to the letter, from Columbia President Minouche Shafik, an individual "hid in the building" at Hamilton Hall until it was closed and let others in. The group's purpose was "occupying the building," the letter read.

Two security guards were inside the building at the time, and the university said in the letter to the NYPD they were able to "secure their release."

"We believe that while the group who broke into the building includes students, it is led by individuals who are not affiliated with the University," the letter read. "The individuals who have occupied Hamilton Hall have vandalized University property and are trespassing."
Addressing the encampment on the school's Morningside campus, the university told police discussions had been carried out with group representatives, but on Sunday, they "reached an impasse."

At that time, the university says it told the group they did not have permission to "occupy spaces on campus" and were "in violation" of school rules and policies.
On Monday morning, the protesters were told they would be suspended if they didn't disperse by Monday at 2 p.m. ET.

The university said in its Tuesday night NYPD letter that those in the encampment were "suspended" and "not authorized to be on University property and are trespassing."

The university said it believed the actions of those in the protest were escalating. "These activities have become a magnet for protesters outside our gates which creates significant risk to our campus and disrupts the ability of the University to continue normal operations," the letter read.

Columbia's president concluded the letter by asking the NYPD to "help to clear all individuals from Hamilton Hall and all campus encampments."

She further asked police to have a campus presence through May 17 -- graduation is May 15 -- "to maintain order and ensure encampments are not reestablished."

Police moved onto the Columbia University campus a little before 9 p.m. ET and began making arrests.

The NYPD also used a vehicle with an extendable roof ramp to help officers breach Hamilton Hall from an upper floor. From there, the police cleared the building.

The campus encampment and hall were cleared before 11:30 p.m.

-ABC News' Jolie Lash, Aaron Katersky and Joshua Hoyos