A former U.S. Army officer has been charged with passing information relating to nuclear weapons and other military secrets to his Chinese girlfriend, the Justice Department said.
Benjamin Bishop, 59, was arrested Friday at work and appeared in federal court in Honolulu on Monday.
He was formally charged with "willfully communicating national defense information to a person not entitled to receive such information."
Court documents identified the woman as a 27-year-old Chinese citizen. Her name was not disclosed and she has not been charged. She was in the United States legally on a student visa, authorities said.
Court documents do not accuse the woman of spying, but an affidavit notes that Bishop met her at a conference in Hawaii where she may have been attempting to target individuals with access to classified information.
Investigators say Bishop began a romantic relationship with her in June 2011 and sought to hide it from authorities.
Bishop, who had top-secret clearance, is also charged with unlawfully retaining classified documents in his home.
He will remain in custody pending a detention hearing on Friday. If convicted, Bishop faces up to 20 years in prison.
"The arrest of Mr. Bishop is just the first step in what is going to be a long process and we are actively continuing the investigation to determine the roles of all those involved in this case," U.S. Attorney Florence Nakakuni said.
Bishop's court-appointed lawyer, Birney Bervar, said the charges were devastating for her client.