The case of a California woman who said she was kidnapped for ransom only to have police call it a hoax took another bizarre twist Monday when federal prosecutors announced they charged a disbarred Harvard-trained lawyer with her abduction.

Matthew Muller, of Orangevale, California, was charged last month after he was arrested in South Lake Tahoe in a home-invasion robbery that occurred in the San Francisco Bay Area and had similarities to the kidnapping, the FBI said. The allegations were in an affidavit that was unsealed Monday.

The kidnapping case began when the woman's boyfriend, Aaron Quinn, reported kidnappers broke into the couple's Vallejo home March 23, abducted her and demanded an $8,500 ransom.

Quinn's lawyers have said he awoke to a bright light in his face, and two kidnappers bound and drugged him.

The 29-year-old woman turned up safe two days later in her hometown of Huntington Beach, where she says she was dropped off. She showed up just hours before the ransom was due.

The Associated Press is not naming the woman because she says she was a victim of sexual assault. The FBI says they found no evidence of nonconsensual sex.

After the woman reappeared, Vallejo police said at a news conference the kidnapping was a hoax. Police have since declined to comment other than to say they continue to investigate. A call to Vallejo police was not immediately returned Monday.

Quinn's attorneys maintained the kidnapping was real, and people purporting to be the victim's kidnappers sent an email to Vallejo police demanding they apologize for calling it a hoax and acknowledge they were wrong.

FBI Special Agent Jason Walter said in the affidavit that recently discovered evidence led him to conclude there was probable cause to believe Muller kidnapped the woman.

Investigators who arrested Muller in South Lake Tahoe found a laptop that resembled one Quinn had. A search of a stolen car that was connected to Muller turned up numerous other items, including a water pistol with a flashlight and laser pointer on it. People claiming responsibility for the woman's abduction emailed photos of the items to a newspaper, Walter said.

A cellphone in the car had one of the same photos, and the vehicle's navigation system turned up a Huntington Beach address.

Detectives also found a pair of goggles with a long blond hair in it, the same hair color as the victim's. The goggles were similar to those the woman and Quinn said they were forced to wear during the kidnapping, Walter said.

On Monday, Muller was in custody on charges of attempted first-degree residential robbery and assault in Alameda County, where the home-invasion robbery occurred. A call seeking comment from his attorney, Thomas Johnson, was not immediately returned.

Muller told investigators he served as a Marine from 1995 to 1999 and attended and taught at Harvard University after that, the FBI affidavit said. He said he suffered from psychosis and in 2008 was diagnosed with bipolar disorder, according to the affidavit.

Muller was admitted to practice law in California in May 2011. His state bar profile also shows he attended Harvard Law School.

Muller's license was suspended in 2013 for failing to pay annual dues, records show. Later that year, the state bar filed disciplinary charges against Muller, citing his failure to file a green card application for a client's son. The bar notice states Muller took $1,250 in advance money from the client.

Muller failed to cooperate with the bar's investigation, leading the State Bar Court to recommend his disbarment in January. The state Supreme Court ordered him disbarred in June.

Wilson Purves, a partner with the Kerosky, Purves & Bogue in San Francisco, said Muller worked as an associate at the immigration law firm for a year before it terminated his employment in 2012. Purves declined to discuss the termination but said there was nothing that stood out about Muller.

"Nothing extraordinary would make me feel that he could be accused of something like this," he said. "I don't know what happened between then and now."