Several students at Quakertown High School were taken into custody on Friday after a student walkout protesting federal immigration enforcement escalated into a confrontation that left at least one teenager bloodied and in handcuffs, according to witnesses and video footage from the scene.

School officials said the episode began shortly before noon, when dozens of students left campus without permission to demonstrate along Front Street in opposition to the policies of U.S. Immigration and Customs Enforcement. What followed, according to videos posted widely on social media, was a chaotic scene involving students, an unidentified man, and local police officers.

By late afternoon, authorities had released few details about what prompted officers to intervene or how many students were detained.

In a letter to parents, Lisa Hoffman, the acting superintendent of the Quakertown Community School District, said 35 students left school grounds at about 11:30 a.m. to stage the protest. She said district officials were informed by the Quakertown Police Department that the students were “engaging in unsafe and disruptive behavior,” though she did not elaborate on what that behavior entailed.

Videos circulating online offer a fragmented glimpse of the confrontation. In one clip, a man is seen grabbing a teenage girl and placing her in a chokehold. A male student rushes in and strikes the man, after which police officers move in and take the student into custody. Other footage shows protest signs scattered across the sidewalk, speckled with blood, and a teenage girl in handcuffs with blood visible along the side of her face.

It remains unclear what role the man played in the altercation or what specific actions led police to detain the students. Messages seeking comment from the police department, the Bucks County District Attorney’s Office, and the school district were not immediately returned Friday afternoon.

By late afternoon, the number of students taken into custody had not been disclosed, and school officials had not said whether any would face disciplinary action.