A Chinese woman detained by U.S. border officers for overstaying a visitor visa died by suicide while being held at a border patrol station in Arizona, a Democratic member of Congress said.

The woman had been taken into custody in California after officers determined that she had overstayed a visitor visa, Rep. Pramila Jayapal of Washington said in a statement, citing the U.S. Customs and Border Protection agency. She was transferred to a patrol station in Yuma, Arizona, the statement said.

Jayapal, a ranking member of the House subcommittee overseeing immigration, said initial reports from the agency had raised concerns about whether officers had properly conducted welfare checks on the woman.

While welfare checks were logged, officials at the agency investigating the death could not verify whether the checks had actually happened, Jayapal said.

“There is no excuse for why agents cannot verify if some of the necessary welfare checks occurred — or why some of the documented welfare checks were incorrectly reported,” Jayapal said.

— The New York Times