A top U.S. Justice Department official says the department is investigating whether Columbia University concealed “illegal aliens” on its campus.

Federal agents searched two student residences at Columbia University, its interim president said, a week after immigration agents detained Mahmoud Khalil, a leader of last year's campus protests, who the Trump administration wants to deport.

Columbia Interim President Katrina Armstrong said Thursday that the agents had search warrants and no one was arrested or detained in the student resident search.