In a statement, DHS said he posed significant national security concerns, but declined to clarify those concerns when asked.

“ICE HSI (Homeland Security Investigations) made this arrest in accordance with the State Department’s revocation of Doroudi’s student visa. This individual posed significant national security risk concerns,” the statement read. According to The Crimson White, the DHS spokesperson did not explain what those national security risk concerns entailed.

The University of Alabama confirmed on Wednesday that a doctoral student has been detained off-campus by U.S. Immigration and Customs Enforcement. Reports from The Crimson White, the university’s student newspaper,