U.S. immigration agents arrested a Palestinian graduate student who has played a prominent role in pro-Palestinian protests at New York's Columbia University as part of U.S. President Donald Trump's promised crackdown on some anti-Israel activists.

A federal judge has blocked the deportation of a pro-Palestinian activist, involved in student protests at Columbia University, following his arrest by Immigration and Customs Enforcement over the weekend.

Mahmoud Khalil's attorney says he was detained by immigration officers who claimed his student visa was revoked, despite him not being on one. His whereabouts remain unknown.