Two University of Arizona students facing criminal charges for protesting US border patrol officers said they have been “harassed” by the police, subject to violent threats and no longer feel safe going to class.

In their first statement since police announced criminal charges for their non-violent demonstration, Denisse Moreno Melchor, 20, and Mariel Alexandra Bustamante, 22, told the Guardian that they felt the “campus is unsafe” for them, and that the administration has prioritized defending border patrol over protecting its undocumented students.

“The backlash we have received since speaking out has been overwhelming and violent. We are now being investigated and harassed by the University of Arizona police department, and criminally prosecuted,” the two students said in a joint statement. “This campus is unsafe in general, however that has now been heightened since the investigation started.”

Melchor and Bustamante have received national attention and attacks from rightwing and anti-immigrant groups since an on-campus protest at a 19 March student club event where border patrol agents were giving a presentation. A group of protesters chanted outside the meeting, calling the agents “murderers”, according to the Arizona Republic newspaper.

This week, the university announced that Melchor and Bustamante were both facing criminal charges as a result of their protests, with police issuing them misdemeanor citations for “interference with the peaceful conduct of an educational institution”. Melchor was also cited for “threats and intimidation”. The charges could carry up to six months of jail time.

On Thursday, the university said a third student, 27-year-old Marianna Ariel Coles-Curtis, would also be charged with interference at an educational institution.

The charges, along with the administration’s statement expressing support for border patrol and saying “disruption” was not protected by free speech, sparked widespread criticisms from civil liberties groups, lawmakers, immigrant rights activists and professors.

“I’m feeling really unsafe and super depressed and anxious,” Bustamante said by phone on Thursday, noting that she is supposed to graduate next month and doesn’t know how the charges could affect her degree and future. “I’m just scared and worried.”

Bustamante, who majors in anthropology and law and wants to go to law school, said a student center where she interns had to be evacuated due to death threats called in against her and Melchor: “I don’t know where I’m safe … I’m trying not to keep a routine.”

Melchor, who is a double major in Mexican American studies and Spanish translation and interpretation, said in an interview that police detectives showed up at her home last week and repeatedly called her. She said when she went to the police station on Monday and received her citation, law enforcement had a warrant for her phone and seized it – and still haven’t returned it.

“I was blindsided,” she said. “I just feel like I’m being criminalized for being a person of color … I’ve been afraid to go to classes.”

There have also been threats made to the Mexican American studies department, the university said.

Bustamante said police showed up at her mother’s home and called her father.

“This is just outrageous to us. We’re not sure how this escalated the way it did. It’s alarming,” she said.

Their joint statement talked about the “increased militarization of the border”, adding: “The presence of border patrol on campus is harmful to students for many reasons. They are an entity that perpetuate violence upon and criminalize Brown, Black and Indigenous communities … Families have been taken from their homes, on routine stops, and on the street.”

Border patrol has faced growing protests across the country surrounding Donald Trump’s anti-immigrant agenda, including the family separation crisis, the detention of children, deaths of migrants and alleged sexual assaults by agents.

Robert C Robbins, the university president, praised border patrol officers in his original letter announcing charges against the students. Robbins also met with border patrol to discuss the protest.

Melchor and Bustamante noted that Art Del Cueto, a border patrol union official who originally advocated that the students be investigated, had made offensive remarks in a radio interview about them.

Del Cueto said on air that if students on campus were worried about the presence of border patrol, “send me the names of the actual illegal aliens at the school and their addresses and I will be glad, on behalf of the border patrol union, to send any type of information when agents are going to be at their school”, prompting a laugh from the host.

“We take this as a threat, and not a joke,” the two students said in their statement. “It is alarming that the University of Arizona seems to be responding to pressure from a person who uses such threatening and dehumanizing language.”

Bustamante, who is from Nogales, Arizona, along the border, said she felt obligated to speak up for undocumented people given the privilege she has as a citizen.

“I’m always using my voice. That’s a must as a Latina who has citizenship,” she said. “I never thought I’d face repercussions for doing so.”

Coles-Curtis, the graduate student facing charges, said in an interview that she is also an instructor, and that some of her students have spoken about the direct harm they have faced from immigration authorities.

“Students have experienced intense trauma with border patrol. Students have seen their family members taken away from them,” she said. “It’s very clear that the university is much more concerned about its relationship with border patrol than protecting its own students.”

A university spokesman, Chris Sigurdson, told the Guardian on Thursday that no additional students would be charged. He declined to comment on the specific actions of the students that led to the criminal citations, saying only that police had watched videos of the incident and chose the “appropriate” charges.

He declined to say whether the students would face any disciplinary consequences.

The university was also monitoring and investigating threats against students, the spokesman said.