A group of U.S. citizens returning to Miami International Airport from Cuba, where they joined more than 1,500 delegates from 63 countries at an August 10-13 colloquium marking the 100th anniversary of Fidel Castro's birth, were held and questioned by U.S. officials over the weekend of August 15-16. Some travelers were required to surrender their cell phones, laptops, tablets and other electronic devices for inspection, according to U.S. officials who spoke to The Associated Press. Everyone was later released and allowed to enter the United States, with no criminal charges filed, though officials said travelers who had conducted business with Cuban government entities, such as hotels or restaurants, could still face legal consequences if a subsequent investigation finds they violated U.S. sanctions.