Within days of the Pulse nightclub shooting June 12 in Orlando, Fla., in which Omar Mateen killed 50 people, Hicks indicated that he would likely die in the U.S. and subsequently discussed the means by which he planned to carry out an attack within the U.S, the release said. During one of these online communications, Hicks sent a government source a document containing detailed instructions on how to make explosives, according to the U.S. Attorney's office.