A former U.S. Secret Service Special Agent involved in the Silk Road investigation is suspected of pilfering $700,000 worth of bitcoin – after he previously pleaded guilty to the theft of $820,000 in bitcoin and received a five-year prison sentence, according to Network World.

Shaun Bridges, a forensics and technical expert on the task force that in October 2013 took down Silk Road, an online black market, pled guilty to money laundering and obstruction of justice. He is now suspected by the government of two subsequent thefts of bitcoin.

He is believed to have kept a private crypto key allowing him access to an account holding $700,000 in bitcoin taken in the Silk Road case. His expertise in forensics enabled him to anonymize account records, plus he attempted to disguise his identity and obtain false documents, the accusation said.

Silk Road founder Ross William Ulbricht was sentenced to life in prison.