Mahmoud Khalil, a Palestinian refugee raised in Syria, was taken into custody from his university-owned apartment near the Ivy League campus in New York. Mr Khalil played a key role in last spring’s pro-Palestinian student encampment protests at Columbia, part of nationwide demonstrations against Israel’s war on Gaza. He has since been transferred to an immigration detention centre in Elizabeth, New Jersey. The arrest comes amid the Trump administration’s intensified crackdown on student activists critical of Israel. President Donald Trump has vowed to deport foreign students and imprison protesters involved in demonstrations against Israeli’s war in Gaza. On Friday, the administration announced it would cut $400 million in grants and contracts to the university, accusing it of failing to address antisemitism on campus. He had also been under investigation by Columbia’s newly formed Office of Institutional Equity, which was tasked with reviewing students who criticised Israel. The committee reportedly sent disciplinary notices to students for activities such as social media posts and participation in unauthorised protests. Under US law, only an immigration court can revoke a green card, not government agencies. However, Secretary of State Marco Rubio intends to revoke visas of foreign nationals deemed to support Hamas or other terrorist groups, using artificial intelligence (AI) to identify individuals.