For hours Tuesday night, a group of 80-some protestors maintained a camp at the University of Arizona’s Main Gate, backed up against the historic volcanic wall and protected by scraps of wood, panels of metal, umbrellas and pop-up shades.

However, more than three hours after University of Arizona police officials warned they would make arrests if the group of pro-Palestinian supporters didn’t abandon their camp after a 10:30 p.m. curfew order, dozens of officers in riot gear smashed their way into the gathering. Police used pepper balls and rubber bullets to push the crowd off campus and onto Park Avenue. 

Four people were arrested, with no serious injuries reported.

UA officials took a hard line against future demonstrations Wednesday. 

Lasting at least through May 15, UAPD will take a zero-tolerance approach, acting “swiftly and decisively to enforce our campus use policy, which can include issuing no warnings before taking action,” UA President Robert Robbins said in a press release.

“While freedom of speech and free expression are encouraged at our university, we will not allow students, faculty, staff, or outside agitators to violate the law or our policies and put anyone at risk,” he said. “We will strictly enforce our campus use policies,” including a ban on shade structures and unpermitted large gatherings.

The camp formed around 3 p.m. Tuesday and expanded throughout most of the evening. Some protestors pulled fencing from a nearby construction site and used the materials to made a paddock around their camp, however,  a few hours later, UA facilities officials took the fencing back. Later protestors built up the flanks of their camp, as people repeatedly drove up Park to deliver materials, including food, water and one large sofa. 

Before the 10:30 p.m. curfew deadline, UA officials, including Steve Patterson, the chief safety officer, his deputy Eric Kazmierczak and spokeswoman Tamra Ingersoll arrived. Also there was Chrissy Lieberman, the assistant dean of students, who read the first warning before handing a public address microphone over to a UAPD police sergeant, who repeated the statement dozens of times over the hours before police pushed into the camp. 

At the scene as well was UAPD Chief Chris Olson.

At one point, police warned they would use a Long-Range Acoustic Device, a very loud speaker that can produce a wave of noise to overwhelm crowds. The devices can cause hearing damage in unprotected people close to it. However, it’s not clear whether the LRAD was used early Wednesday morning. 

As the UAPD sergeant repeated the statement that the crowd should leave, the group tucked into their ad-hoc fortress made jokes, yelled threats and tossed water bottles at police and a crowd of onlookers forming up behind them on Park Ave. Some chanted “If you come in, we will fight you!”

Outside the perimeter, some people yelled “From the river to the sea, Palestine will be free.”

Police twice attempted to push into the camp. The first time, they pulled apart one section of wall, pulling away a cooler and a panel. Later, another officer tried the same flank, but left after people tossed water bottles over the barriers.

At 11:07 p.m., the UA sent out a push alert, telling people UAPD was “responding to an unlawful assembly at University/Park. Leave and avoid the area.” At 12:11 a.m, they announced Park Avenue would be closed to traffic.

Outside the camp and the police tape, dozens of people—some clearly intoxicated—began to watch and record video from their phones. Some yelled in support of the protestors, while others jeered.

At 12:30 a.m., the UA sent out a new alert, telling people “Police may deploy chemical irritant munitions. Follow the orders of police. Leave the area immediately.”

The UA announced the final order at 2 a.m.: “University of Arizona President Robert C. Robbins has directed university officials and the University of Arizona Police Department to immediately enforce campus use policies and all corresponding laws without further warning.”

Robbins, himself under fire and being pushed out of his position due to the UA’s budget mess, later said that “law enforcement had little choice but to take significant measures” such as firing rubber bullets and using pepper balls to quell the crowd.

More than 150 officers were at the scene, including deputies with the Pima County Sheriff’s Department’s tactical team and Arizona state troopers.

“The UAPD is supported by members of the Tucson Police Department, Pima County Sheriff’s Office and the state’s Department of Public Safety. The university will continue to act in the best interests of our students, faculty and staff to ensure their safety,” UA officials said.

Four people were arrested. One person was injured, and a medic from the protestors bandaged his arm.

All four face charges of criminal trespassing, while one faces a charge of aggravated assault on an officer, Robbins said Wednesday afternoon.

“One was an undergraduate student, another a graduate student, and two were unaffiliated with the university,” he said in a press release.

After forcing the protestors off the UA campus and onto the adjacent street, DPS troopers used three vehicles to back a line of dozens of officers, who surged forward, using chemical irritants and grabbing at protestors. One man was dragged between two vehicles and held to the ground. 

As the police made arrests, some bystanders cheered. “Yeah, fuck ’em up,” yelled one man. “Go get ’em boys.”

Others in the crowd yelled “Shame on you. Shame!”

By 3:22 a.m., the UA announced the situation was “all clear.”

After clearing the crowd, police retreated to UA’s Centennial Hall for a debrief.

During a demonstration against the arrests at the UA campus on Wednesday afternoon, Harlow Perkins, one of the group’s organizers, said those arrested were released in the morning.

The protest at the UA was one of dozens on college campuses across the nation as students and community members have sought to protest Israel’s war in Gaza. The UA in part has faced two protests in as many days as people protest the UA’s relationship with Raytheon, the Israeli military defense contractor Elbit, and the construction manufacturer Caterpillar.

A similar protest at Northern Arizona University was also broken up Tuesday night, and police broke up one at Arizona State University, arresting at least 15 students.

Raytheon has become a lightning rod for protests because the defense contracting giant produces weapons, including missiles and other munitions destined for the Israel Defense Force, which has hammered Gaza after the militant group Hamas launched an attack on Oct. 7. Since the attack, which left 1,400 people dead, the Israeli military invaded the Palestinian area, killing as many as 34,000 people, the majority of them women and children, the Guardian reported. Another 77,000 people have been wounded.

In November, Pima County Sheriff’s deputies arrested 20 people, including a reporter during a protest against Raytheon at the UA Tech Park.