WASHINGTON • A young wo-man identified as having taken part in the storming of the US Capitol reportedly stole a laptop belonging to top Democrat Nancy Pelosi and hoped to sell it to a Russian spy agency, according to a Federal Bureau of Investigation (FBI) criminal complaint.

The complaint, filed late on Sunday in the US District Court in Washington, seeks the arrest of Riley June Williams of Pennsylvania on grounds including "violent entry and disorderly conduct on Capitol grounds". Her whereabouts are unknown.

Relying on several photos and videos of the chaotic Jan 6 intrusion, an FBI agent said Williams was seen near the office of House Speaker Pelosi.

A witness, identified in the court document only as W1 but who claimed to be "the former romantic partner of Riley June Williams", alleged that Williams planned to send the laptop to a friend in Russia to sell it to the SVR foreign intelligence agency.

That sale "fell through for unknown reasons, and Williams still has the computer device or destroyed it", according to the affidavit.

It was unclear whether a laptop belonging to Ms Pelosi was actually stolen.

The FBI said it was continuing to investigate.

Several videos show the woman believed to be Williams actively directing fellow rioters, urging them "upstairs, upstairs, upstairs".

The complaint said Williams' mother in the city of Harrisburg was shown pictures taken in the Capitol, and that confirmed a thin, bespectacled brown-haired woman in several pictures was her.

Williams had travelled to Washington with her father, though the two were separated during the chaos that day.

The complaint said that after Williams returned home, she packed a bag and told her mother she was leaving "for a couple of weeks".

"It appears that Williams has fled," the complaint said.

AGENCE FRANCE PRESSE