Mahmoud Khalil, a Columbia University graduate student and Syrian immigrant of Palestinian descent, was detained by federal agents after being accused of leading activities aligned with Hamas, an allegation he denies. Khalil had been a vocal leader in student protests against the war in Gaza, often appearing unmasked while many other international students wore masks to protect their visas. His detention has sparked outrage from friends and family, who argue that his activism was a result of his personal experiences and opposition to the Syrian government. Critics of the protests have accused Khalil of organizing demonstrations where fliers promoting Hamas were distributed, although his lawyers deny these allegations.