HARRISBURG, PA. -- Federal authorities arrested a woman whose former romantic partner says she took a laptop from House Speaker Nancy Pelosi's office during the riot at the U.S. Capitol earlier this month.

Riley June Williams was arrested Monday, according to a Justice Department official. It's not yet known when her initial court appearance will be.

The FBI said in an arrest warrant Sunday that Williams hasn't been charged with theft but only with illegally entering the Capitol and with disorderly conduct.

FBI officials said a caller claiming to be an ex of Williams said friends of hers showed him a video of her taking a laptop computer or hard drive from Pelosi's office. The caller alleged that she intended to send the device to a friend in Russia who planned to sell it to that country's foreign intelligence service, but that plan fell through and she either has the device or destroyed it. The FBI says the matter remains under investigation.

Pelosi's deputy chief of staff, Drew Hammill, confirmed Jan. 8 that a laptop was taken from a conference room but said "it was a laptop that was only used for presentations."

Williams' mother, who lives with her in Harrisburg, told ITV reporters that her daughter had taken a sudden interest in President Donald Trump's politics and "far-right message boards." Her father, who lives in Camp Hill, told local law enforcement that he and his daughter went to Washington on the day of the protest but didn't stay together, meeting up later to return to Harrisburg, the FBI said.

Williams' mother told local law enforcement that her daughter packed a bag and left before she was arrested, saying she would be gone for a couple of weeks. She also changed her phone number and deleted a number of social media accounts, the FBI said. Court documents don't list an attorney for her.