A list of potential bidders for the Bitcoin auction was accidentally leaked by the US Marshals Service on Wednesday, according to the agency.
The Marshals Service confirmed that it accidentally released the names in an email to update interested parties on the auction's guidelines.
"The US Marshals Service inadvertently sent an email today revealing the email addresses of people who had submitted questions about the Bitcoin auction to a general USMS mailbox that had been created for the auction," Lynzey Donahue, a spokeswoman for the US Marshals, said in an emailed statement.
"The USMS apologizes for this mistake which was in no way intentional," the statement said.
The news was first reported by the New York Times, citing a report from CoinDesk, an online website devoted to Bitcoin.
The US government said last week it plans to auction about 30,000 bitcoins, the electronic currency, valued at about $17.4 million, on June 27 the US Marshals Service said.
FBI seized the bitcoins during a raid in October on the Internet marketplace Silk Road, known as a hub for transactions involving illegal drugs and criminal activities.
The seized bitcoins are part of the civil forfeiture and criminal action brought against Silk Road owner Ross William Ulbrich and the assets of Silk Road, the U.S. Marshals Service said.
CoinDesk has a list of people who inquired about the auction, including Fred Ehrsam, the co-founder of Coinbase, a Bitcoin payment processor, the New York Times said.