Originally posted by the Voice of America. Voice of America content is produced by the Voice of America, a United States federal government-sponsored entity, and is in the public domain. Iran Denies Knowledge of Missing Ex-FBI Agent After Reports He Died RFE/RL Tehran has denied it knows the whereabouts of Robert Levinson after the United States demanded "a complete accounting" of what happened to the retired FBI agent, who is believed to have died in Iranian custody. "Iran has always maintained that its officials have no knowledge of Mr. Levinson's whereabouts, and that he is not in Iranian custody. Those facts have not changed," Alireza Miryousefi, a spokesman for the Iranian mission at the United Nations, said in a Tweet on Thursday. The statement comes in response to a White House statement saying that the U.S. administration believed Bob Levinson may have passed away "some time ago." "Iran must provide a complete accounting of what occurred with Bob Levinson before the United States can fully accept what happened in this case," White House national-security adviser Robert O'Brien said in a statement about the American, who disappeared in Iran 13 years ago, when he was 58. Before that statement, Levinson's family posted on social media that it had received word about his likely fate from the U.S. government. .