WASHINGTON » A Jordanian-born Palestinian convicted in a 1982 airline bombing that killed a Japanese teenager remains in federal immigration custody one year after being released from prison.

Mohammed Rashed, 64, was freed from prison last March after spending more than two decades in custody in Greece and the United States. But as of Wednesday, he remained at a federal immigration detention facility in Batavia, N.Y., where he is awaiting deportation, said Vincent Picard, a spokesman for U.S. Immigration and Customs Enforcement.

Picard declined to comment on why Rashed remained in the United States, except to say that authorities were finalizing his removal from the country. He would not say where Rashed would be sent, though his plea agreement permits him to be deported to a country of his choice upon his release. His lawyers did not immediately return calls seeking comment.

Federal court records show Rashed recently tried to file a motion with a judge under a statute permitting prisoners to challenge their detention. U.S. District Judge Royce Lamberth ordered last month that the document be filed under seal.

Rashed pleaded guilty in Washington’s federal court in 2002 for his role in the Aug. 11, 1982 bombing of Pan Am 830. The bomb, which Rashed had placed beneath a seat cushion before disembarking in Tokyo, exploded over the Pacific Ocean as the plane continued onto Honolulu. One person was killed and more than a dozen others injured. 

He was arrested in Greece in 1988 while traveling on a phony Syrian passport and was convicted there by a three-judge panel. He was released for good behavior in 1996. Two years later the FBI whisked him out of Egypt and returned him to the U.S. for prosecution. 

He was permitted to be released from prison in 2013 as part of his plea agreement in Washington, but detained by immigration officials.

Rashed had been a top lieutenant to Abu Ibrahim, a Palestinian master bomb maker who authorities say orchestrated the Pan Am attack and similar strikes around the world. Ibrahim is currently on the FBI’s list of most wanted terrorists.