Washington (CNN)-

Senior US government officials said Friday that a Chinese scientist who had been hiding in the country’s San Francisco consulate after accusations of visa fraud is now in US custody and also charged that Beijing has been using its diplomatic outposts to run an espionage network to steal intellectual property from US businesses, universities and research centers.

Tang Juan, a researcher who said she was focusing on biology, “was a fugitive from justice until last night,” a senior Justice Department official said, but has now been charged in Sacramento. The circumstances of Tang’s arrest were not clear, but she has not been charged with espionage.

US officials made the announcement just hours before Washington’s deadline for Beijing to shutter its consulate in Houston, a move that triggered China to retaliate Friday by demanding the US close its consulate in Chengdu.

Prosecutors earlier this week said that Tang concealed her connection to China’s military in order to enter the US, lied to federal investigators about those links and subsequently tried to avoid arrest by taking refuge in the San Francisco consulate.

During an interview with FBI agents on June 20, “Tang denied serving in the Chinese military, claimed she did not know the meaning of the insignia on her uniform, and that wearing a military uniform was required for attendance at FMMU because it was a military school,” attorneys wrote in a July 20 court filing.

But in a search of her home and electronic media, FBI investigators “discovered photographs of her in the uniform of the Civilian Cadre of the Chinese People’s Liberation Army (PLA)” and that she had been employed as a researcher at the Fourth Military Medical University.