A Taiwan-born Navy officer who became a naturalized U.S. citizen faces charges of espionage, attempted espionage and prostitution in a highly secretive case in which he is accused of providing classified information to China and Taiwan, U.S. officials said.

The Navy examined the charges against Lt. Cmdr. Edward C. Lin in a preliminary military justice hearing on Friday. The service did not release his identity, but a U.S. official disclosed it Sunday under the condition of anonymity, citing the sensitivity of the case. Lin’s connection to the case was first reported by USNI News.

The Navy, which has not identified Lin by name, said the officer is assigned to the headquarters for the Patrol and Reconnaissance Group, which oversees maritime patrol aircraft such as the P-8A Poseidon and P-3C Orion spyplanes and the MQ-4C Triton surveillance drone.

A heavily redacted charge sheet released by the Navy states that the officer faces two specifications of espionage and three specifications of attempted espionage. He is accused of communicating secret information “with intent or reason to believe it would be used to the advantage of a foreign nation,” hiring a prostitute for sex, committing adultery by having sex with a woman who was not his wife, not disclosing foreign travel to the U.S. government as required, and lying about it after the fact.

It could not be determined who is serving as Lin’s legal representation from the charge sheet released by the Navy. The military typically discloses the identity of a service member who faces a preliminary “Article 32” hearing like the one involved in this case, but the officer’s name was redacted from the charge sheet released afterward “out of consideration for the service member’s privacy,” said Lt. Cmdr. Timothy Hawkins, a Navy spokesman.

“Prior to a decision for the referral of charges, we are unable to identify the officer at this time,” Hawkins said.

A U.S. official confirmed that Lin’s personal story was highlighted by the Navy in 2008, as he became a naturalized citizen in a ceremony in Honolulu. He and his family came to the United States when he was 14 and spoke little English at the time, he said at the ceremony, according to a Navy account of the event.

“I was barely able to spell ‘ABC.’ The only name that I knew back then as an American name was Eddy,” Lin said at the time. “Eddy was the name of my mother’s dog … I was very fortunate that my mother did not name her dog ‘Fluffy.'”

At the ceremony, Lin thanked other military service members who also were being naturalized for safeguarding their new nation.

“You have recognized that not only do citizens have rights, but citizens also have responsibilities. The responsibility you are performing even now as non-U.S. citizen,” Lin said, according to the Navy account. “Extraordinary events made this nation and our military. People like you, men and women who stepped forward when their nation needed them accomplished these extraordinary events. I thank you for your decision to serve.”

The top flag officer overseeing Lin’s case as convening authority is Adm. Philip S. Davidson, the commander of U.S. Fleet Forces Command in Norfolk. Lin is being held at the Naval Consolidated Brig in Chesapeake, Va. He was arrested about eight months ago, Newsweek reported Saturday.

The case remains under investigation by the Naval Criminal Investigative Service and the FBI. Spokesmen for senior Navy officials, including Navy Secretary Ray Mabus and Adm. John Richardson, chief of naval operations, declined to comment on Sunday. Ed Buice, a spokesman for NCIS, also declined to comment.

This story was first published at 1:39 p.m. and updated with confirmation of Lin’s identity and details about him.

Clarification: A U.S. official told The Washington Post on Sunday that the investigation centers on whether Lin passed military secrets to China. It is actually both China and Taiwan, officials said Monday.