Schiff said detainees are eventually given a list of legal organizations but cannot call the groups. “It’s not meaningful to get a list of attorneys if you can’t call them,” he said after visiting the facility.

He also said he was troubled that lawful permanent residents are among those held there. They can be separated from their families for hours or days, Schiff said, with little ability to challenge what is happening to them.

Airport officials refer to the holding room as an “in-transit lounge.” The facility has drawn increased scrutiny as people are reportedly held there for days rather than hours. Most detainees are green-card holders with prior arrests, and a newspaper investigation found that many were later transferred to Immigration and Customs Enforcement detention.

Schiff said one person was being held at the facility at the time of his visit. A report published Sept. 1 said more than two dozen people had been held there during the year. Customs and Border Protection did not respond to a request for comment.