Protests have erupted over the arrest of an 18-year-old Massachusetts high school student who state officials say was detained by Immigration and Customs Enforcement agents over the weekend while on his way to volleyball practice.

Marcelo Gomes da Silva, a Brazilian national who is a junior at Milford Public High School, was arrested on Saturday, according to a court filing from his attorney.

Students at the high school staged a walkout on Monday in support of Gomes da Silva, holding signs that said “Free Marcelo.” The protest followed community demonstrations at the Milford Town Hall on Sunday calling for his release.

The teen, who is currently in ICE custody, was not the target of the operation but was a collateral arrest, according to ICE officials.

“When we go out into the community and we find others who are unlawfully here, we are going to arrest them,” ICE acting Field Director Patricia Hyde said at a press briefing on Monday. “We’ve been completely transparent with that. He’s 18 years old. He’s unlawfully in this country.”

Gomes da Silva’s father was the actual target of the operation, according to acting ICE Director Todd Lyons. The father, Joao Paulo Gomes-Pereira, was sought because he “has a habit of reckless driving” at speeds over 100 mph, according to the Department of Homeland Security.

Agents made a traffic stop on the father’s vehicle, which Gomes da Silva was driving at the time of his arrest, Lyons said during the briefing. The father has not turned himself in yet, he said.

Gomes da Silva entered the U.S. in 2012 through a student visa, which has since lapsed, according to his attorney. He has no criminal history and is “eligible for and intends to apply for asylum,” his attorney stated in a habeas corpus petition filed Sunday seeking his release.

A federal judge issued an emergency order Sunday afternoon directing the government not to remove Gomes da Silva from the U.S. or to transfer him out of the judicial district of Massachusetts for at least 72 hours. On Monday, a federal judge ordered that the government not transfer the teen out of Massachusetts without first providing the court at least 48 hours advance notice of and reasons for the move.

The ICE detainee locator website lists Gomes da Silva as being in custody but does not list where he is being held. His habeas petition indicates “on information and belief” that ICE is detaining him at a field office in Burlington, Massachusetts.

Massachusetts Gov. Maura Healey said she is “demanding immediate answers from ICE” about the teen’s arrest, where he is being held and “how his due process is being protected.”

“I’m disturbed and outraged by reports that a Milford High School student was arrested by ICE on his way to volleyball practice yesterday,” Healey said in a statement on X on Sunday. “Yet again, local officials and law enforcement have been left in the dark with no heads up and no answers to their questions.”

Kevin McIntyre, the Milford superintendent of schools, said in a statement that the student was detained off-campus, and several parents have also been detained by ICE in recent weeks.

“We are all distraught by this news,” McIntyre said in a statement. “The Milford Public Schools play no part in immigration enforcement and support all of our students and families, including those who are immigrants to the United States. They are members of the community, students in our classrooms, athletes that compete representing Milford, musicians, artists, friends, and neighbors. We will do everything in our power to support our students and families during these difficult times.”

Gomes da Silva was supposed to play in the band at the high school’s graduation on Sunday, Boston ABC affiliate WCVB reported. Some graduates marched from the ceremony to the protest at Milford Town Hall, still in their caps and gowns.

The teen’s friends expressed shock and dismay at his arrest. His girlfriend, Julianys Rentas, told WCVB that he plays drums for her church.

“He’s a member of his community and he’s never done anything wrong,” she told the station while fighting back tears.

U.S. Rep. Jake Auchincloss, who attended Sunday’s rally, also expressed disbelief at the teen’s detainment.

“I don’t see how a kid en route to volleyball, who is an honors student, who’s a musician in the high school band — that kid is not a threat to law and order,” the Democrat told WCVB.

ICE arrested 1,461 “alien offenders” in the region in May as part of a large-scale operation, according to Hyde. Over half — 790 — had “significant criminality as well,” she said.

Pressed by reporters on whether Gomes da Silva was a danger to the community, Lyons said, “I didn’t say he was dangerous. I said he’s in this country illegally.”

“We’re not going to walk away from anybody,” he added.

ABC News’ Luke Barr and James Hill contributed to this report.