A former U.S. defense contractor’s Chinese girlfriend might have coaxed top secret national security information from him, according to documents filed in federal court Monday.

Benjamin Pierce Bishop, 59, is accused of telling his girlfriend classified nuclear secrets and keeping sensitive information at his home in Kapolei, both in violation of federal law.

But Bishop’s girlfriend, who he met at an international military defense conference in Hawaii, remains a mystery. Federal officials won’t say who she is, only identifying her as “Person 1.”

There also doesn’t appear to be any push to bring the woman — who was in the U.S. on a student visa — into custody.

Bishop, meanwhile, is being isolated in a special holding unit at the Federal Detention Center in Honolulu. He was arrested on March 15 at U.S. Pacific Command, where he worked in cyber defense and had top secret security clearance.

The U.S. Attorney’s Office has tried to keep Bishop behind bars until his case goes to trial, describing him as a national security threat because of the information contained in his mind.

A federal magistrate judge initially agreed, relying on highly sensitive materials shared with him behind closed doors.

But U.S. District Court Judge Leslie Kobayashi overturned that decision on April 1, saying Bishop could stay in a halfway house so long as he complied with certain conditions.

Kobayashi explained her reasoning in court records filed Monday, saying that although Bishop’s knowledge poses an “extremely serious” threat to the community there are other, less restrictive avenues to keep him from fleeing the country and funneling top secret information to others.

For instance, she said Bishop could stay at the Mahoney Hale, a community detention center that provides a place for inmates whose sentences are nearly up and are ready to transfer back into society.

Bishop would not be allowed to leave the facility, she said, unless he was accompanied by a “third-party custodian” or his attorney. He’d only be allowed to leave Mahoney Hale for specific purposes, such as religious worship or to participate in his legal defense.

Kobayashi’s ruling revealed that the federal government believes that Bishop had taken information from USPACOM “parly at the direction of his girlfriend.” Kobayashi also noted that the U.S. Attorney’s Office believes it has “substantial evidence” against Bishop because he supposedly admitted to disclosing information to his girlfriend and that there was a record of his email and telephone communications with her.

Prosecutors tried to convince Kobayashi that she should keep Bishop locked up because he lied about his “extramarital affair with a foreign national” and didn’t tell his bosses about a 2003 arrest for soliciting a prostitute.

This compromised his character, they said, and further proved he couldn’t be trusted.

They also didn’t think he could be kept from contacting his girlfriend or others if allowed out of FDC because of what Kobayashi summarized in her ruling as “‘digital age’ threats of undetected communication via secret email, Facebook and Twitter accounts, or disposable cell phones.”

Bishop will not be allowed to access the internet at Mahoney Hale. His telephone and mail communications will also be monitored.

Other restrictions may be placed on Bishop when he leaves the FDC. Those will be determined at a later hearing.

Read Kobayashi’s order here: