The US Homeland Security has apologised to Civil Aviation Minister Praful Patel for being questioned by the immigration authorities in Chicago. Apologising over the issue, the US Secretary of Homeland Security, Janet Napolitano gave an assurance that the US will do whatever required to make necessary amendments to prevent any such incidents in the future. Mr Patel, who was in Chicago on a private visit and flew to Montreal for attending an official engagement, was stopped and quizzed at the O'Hare airport. He was questioned as his name and date of birth happened to match with that of another Praful Patel, who is reportedly on US' watch list.