Rubio’s letter notified DHS that he had revoked both targets’ visas, setting in motion plans for U.S. Immigration and Customs Enforcement to arrest and attempt to deport them, according to a senior DHS official and another U.S. official who spoke on condition of anonymity to describe how the operation against Khalil took shape.

Trying to deport Khalil for demonstrating against Israel is an obvious violation of his rights and an attempt to intimidate others, they say.

"I think it would be very devastating for me and for him to meet his first child behind a glass screen," his wife, who is eight months pregnant, told Reuters.

Noor Abdalla, wife of detained Palestinian Columbia University student Mahmoud Khalil, says she thought her husband didn't have to worry about ICE.

Two days before U.S. agents arrested Mahmoud Khalil, the Columbia University student and Palestinian activist asked his wife if she knew what to do if immigration agents came to their door. Noor Abdalla,