Washington ? Former President Jimmy Carter was preparing to leave for North Korea today to try to gain the freedom of an American imprisoned for illegally entering the communist nation, U.S. officials said Monday night.

North Korea agreed to release Aijalon Mahli Gomes if Carter were to come to bring him home, a senior U.S. official told The Associated Press. Gomes, of Boston, who was arrested on Jan. 25 after entering North Korea, was sentenced in April to eight years in prison and fined $700,000.

Carter was expected to spend a single night in North Korea and return with Gomes on Thursday, a second U.S. official said. Both officials spoke on condition of anonymity because of the sensitivity of the situation.