The trove of digital currency was grabbed during the Silk Road takedown in 2013.
Ross Ulbricht was convicted for his role in creating a platform for selling illegal drugs.
The hidden online sites are facing their "most serious attack" ever, one operator says.
The day after the FBI took down the infamous Silk Road 2, more sites are going offline.
His concern follows reports that illicit drug listings online have nearly doubled.
The U.S. Marshals Service is selling off nearly 30,000 bitcoins seized on Silk Road.
He tried to steal hundreds of thousands of dollars while targeting the online drug market.
A judge ruled the revelation of rogue agents on the investigation did not change the facts.
Ross Ulbricht could spend the rest of his life behind bars for the shadowy online market.
The online black market, like its predecessor, specialized in selling drugs.
An official accidentally cc'd 40 bidders on a message that meant to bcc the recipients.
Rep. Jared Polis sends regulators a tongue-in-cheek letter about the dangers of U.S. money.