The U.S. Department of Homeland Security accused Ozturk, a Turkish national, of "activities in support of Hamas."

Secretary of State Marco Rubio defended the detention of a foreign Ph.D. student at Tufts University on Tuesday. Rumeysa Ozturk, a Turkish national, was seen in a video arrested by plain-clothes federal officers and taken away in an unmarked van.

Ozturk was suddenly arrested by plainclothes federal agents Tuesday in an incident captured by a surveillance camera.