AUSTIN, TEXAS -- Police tangled with student demonstrators in Texas and California while new encampments sprouted Wednesday at Harvard and other colleges as school leaders sought ways to defuse a growing wave of pro-Palestinian protests.

At the University of Texas at Austin, hundreds of local and state police 鈥 including some on horseback and holding batons 鈥 clashed with protesters, pushing them off the campus lawn and at one point sending some tumbling into the street. At least 20 demonstrators were taken into custody at the request of university officials and Texas Gov. Greg Abbott, according to the state Department of Public Safety.

A photographer covering the demonstration for Fox 7 Austin was arrested after being caught in a push-and-pull between law enforcement and students, the station confirmed. A longtime Texas journalist was knocked down in the mayhem and could be seen bleeding before police helped him to emergency medical staff who bandaged his head.

And at the University of Southern California, police got into a back-and-forth tugging match with protesters over tents, removing several before falling back. At the northern end of California, students were barricaded inside a building for a third day at California State Polytechnic University, Humboldt. The school shut down campus through the weekend and made classes virtual.

Harvard University in Massachusetts had sought to stay ahead of protests this week by limiting access to Harvard Yard and requiring permission for tents and tables. That didn't stop protesters from setting up a camp with 14 tents Wednesday following a rally against the university鈥檚 suspension of the Harvard Undergraduate Palestine Solidarity Committee.

Columbia university protests

Students protesting the Israel-Hamas war are demanding schools cut financial ties to Israel and divest from companies enabling its monthslong conflict. Dozens have been arrested on charges of trespassing or disorderly conduct. Some Jewish students say the protests have veered into antisemitism and made them afraid to set foot on campus.

Columbia University averted another confrontation between students and police earlier in the day. The situation there remained tense, with campus officials saying it would continue talks with protesters for another 48 hours.

On a visit to campus, U.S. House Speaker Mike Johnson, a Republican, called on Columbia University President Minouche Shafik to resign 鈥渋f she cannot bring order to this chaos.鈥

鈥淚f this is not contained quickly and if these threats and intimidation are not stopped, there is an appropriate time for the National Guard,鈥 he said.

Shafik had set a midnight Tuesday deadline to reach an agreement on clearing an encampment, but the school extended negotiations, saying it was making 鈥渋mportant progress."

On Wednesday evening, a Columbia spokesperson said rumors that the university had threatened to bring in the National Guard were unfounded. 鈥淥ur focus is to restore order, and if we can get there through dialogue, we will,鈥 said Ben Chang, Columbia鈥檚 vice president for communications.

Columbia graduate student Omer Lubaton Granot, who put up pictures of Israeli hostages near the encampment, said he wanted to remind people that there were more than 100 hostages still being held by Hamas.

鈥淚 see all the people behind me advocating for human rights," he said. 鈥淚 don鈥檛 think they have one word to say about the fact that people their age, that were kidnapped from their homes or from a music festival in Israel, are held by a terror organization.鈥

Harvard law student Tala Alfoqaha, who is Palestinian, said she and other protesters want more transparency from the university.

鈥淢y hope is that the Harvard administration listens to what its students have been asking for all year, which is divestment, disclosure and dropping any sort of charges against students," she said.

Police first tried to clear the encampment at Columbia last week, when they arrested more than 100 protesters. The move backfired, acting as an inspiration for other students across the country to set up similar encampments and motivating protesters at Columbia to regroup.

On Wednesday about 60 tents remained at the Columbia encampment, which appeared calm. Security remained tight around campus, with identification required and police setting up metal barricades.

Columbia said it had agreed with protest representatives that only students would remain at the encampment and they would make it welcoming, banning discriminatory or harassing language.

On the University of Minnesota campus, a few dozen students rallied a day after nine protesters were arrested when police took down an encampment in front of the library. U.S. Rep. Ilhan Omar, whose daughter was among the demonstrators arrested at Columbia last week, attended a protest later in the day.

A group of more than 80 professors and assistant professors signed a letter Wednesday calling on the university's president and other administrators to drop any charges and to allow future encampments without what they described as police retaliation.

They wrote that they were 鈥渉orrified that the administration would permit such a clear violation of our students鈥 rights to freely speak out against genocide and ongoing occupation of Palestine.鈥

Israeli Prime Minister Benjamin Netanyahu lashed out at the pro-Palestinian demonstrations on U.S. college campuses in a video statement released Wednesday, saying the response of several university presidents has been 鈥渟hameful鈥 and calling on state, local and federal officials to intervene.

Students at some protests were hiding their identities and declined to identify themselves to reporters, saying they feared retribution. At an encampment of about 40 tents at the heart of the University of Michigan鈥檚 campus in Ann Arbor, almost every student wore a mask, which was handed to them when they entered.

The upwelling of demonstrations has left universities struggling to balance campus safety with free speech rights. Many long tolerated the protests, but are now doling out more heavy-handed discipline, citing safety concerns.

At New York University this week, police said 133 protesters were taken into custody and all had been released with summonses to appear in court on disorderly conduct charges. More than 40 protesters were arrested Monday at an encampment at Yale University.

Perry reported from Meredith, New Hampshire. Contributing to this report were Associated Press journalists in various locations including Joey Cappelletti, Will Weissert, Larry Lage, Steve LeBlanc, Dave Collins, Jim Salter, Haven Daley, Jesse Bedayn, John Antczak, Julie Walker and Joseph Krauss.