Relations between Libya and the United States under President Reagan were continually contentious, beginning with the Gulf of Sidra incident in 1981; by 1982, Libyan leader Muammar Gaddafi was considered by the CIA to be, along with USSR leader Leonid Brezhnev and Cuban leader Fidel Castro, part of a group known as the "unholy trinity" and was also labeled as "our international public enemy number one" by a CIA official. These tensions were later revived in early April 1986, when a bomb exploded in a Berlin discothèque, resulting in the injury of 63 American military personnel and death of one serviceman. Stating that there was "irrefutable proof" that Libya had directed the "terrorist bombing", Reagan authorized the use of force against the country. In the late evening of April 15, 1986, the United States launched a series of airstrikes on ground targets in Libya.