SEATTLE >> A federal judge upheld a decision not to release a Mexican man arrested near Seattle, despite his participation in a program designed to protect those brought to the U.S. illegally as children.

In the decision Friday, U.S. District Judge Ricardo S. Martinez said “many questions remain regarding the appropriateness of the government’s conduct” in the arrest of 24-year-old Daniel Ramirez Medina. But the judge said he should challenge his detention in immigration court, a separate legal system run by the U.S. Justice Department.

The order upheld a previous decision by U.S. Magistrate Judge James P. Donohue.

Immigration agents arrested Ramirez Feb. 10 at a suburban apartment complex where they had gone to arrest his father, a previously deported felon. Agents said Ramirez acknowledged affiliating with gangs.

Ramirez, who is being held at a federal detention center in Tacoma, denies the claims. He has no criminal record and twice passed background checks to participate in the Deferred Action for Childhood Arrivals program, which allows people brought to the U.S. illegally as children to stay in the country and work.

Federal authorities said the arrest of Ramirez was routine.

However, it was one of several arrests that have left immigration activists fearing an erosion of protections under the DACA program.

U.S. Immigration and Customs Enforcement agents in Portland, Oregon, on Sunday arrested Francisco J. Rodriguez Dominguez, a DACA participant who was brought to the U.S. from Morelia, in Mexico’s Michoacan state, at age 5.

The American Civil Liberties Union of Oregon said in a written statement that last December, he entered a diversion program following a drunken driving arrest, and that he had attended all his court dates and required meetings.

“Despite Francisco’s best efforts to make good on his mistake, ICE has taken the position that even a misdemeanor DUI eligible for diversion is enough to end DACA status,” Andrea Williams, executive director of Causa Oregon, an Oregon immigrant rights organization, said in the statement. “This policy is tearing apart his family, our communities, and does nothing to keep us safer.”

The federal agency did not immediately return an email seeking comment Monday.

About 750,000 immigrants have enrolled in the program since President Barack Obama instituted it in 2012.

Ramirez’s lawyers have sought to keep his case out of federal immigration court, which they say is ill-equipped to handle his claims that his arrest violated his constitutional rights to due process and to be free from unreasonable seizure.

They have not challenged the deportation proceedings initiated by the government but have sought his release on constitutional grounds.

The judge noted that the Department of Homeland Security has the authority to detain people who are in the U.S. illegally during their deportation proceedings.

That means Ramirez would not be entitled to release even if the court found his rights were violated, Martinez said.

“He has placed himself in the tenuous position of arguing that his arrest and detention have violated his constitutional rights, while also asserting that he is not challenging the revocation of his DACA status or ‘anything that has to do with the removal proceedings themselves,’” Martinez wrote.

The judge added that the case is unusual and he had sympathy for Ramirez’s situation.

Ramirez’ lawyers are disappointed that he remains in custody and are trying to determine how to win his release, Manny Rivera, a spokesman for the lawyers, said Monday.

Ramirez is originally from the city of La Paz in Mexico’s Baja California Sur state.