A major US immigration enforcement operation has put 30 Indian truck drivers at the centre of a deportation battle. As part of "Operation Checkmate", US Customs and Border Protection arrested dozens of individuals allegedly living and working in the country illegally while operating commercial vehicles. Authorities say many of the drivers were using expired or invalid work authorisation documents. The crackdown comes amid growing scrutiny of foreign truck drivers following a series of fatal crashes and tighter regulations in the US trucking industry. Here's what Operation Checkmate is, why Indian nationals were targeted and what could happen next.