Popular bitcoin exchange Bitfinex has been hacked and the site has been taken down while the exchange investigates exactly what happened and cooperates with law enforcement.
We are investigating the breach to determine what happened, but we know that some of our users have had their bitcoins stolen. We are undertaking a review to determine which users have been affected by the breach. While we conduct this initial investigation and secure our environment, bitfinex.com will be taken down and the maintenance page will be left up.
[…] As we account for individualized customer losses, we may need to settle open margin positions, associated financing, and/or collateral affected by the breach. Any settlements will be at the current market prices as of 18:00 UTC. We are taking this necessary accounting step to normalize account balances with the objective of resuming operations. We will look at various options to address customer losses later in the investigation. While we are halting all operations at this time, we can confirm that the breach was limited to bitcoin wallets; the other digital tokens traded on Bitfinex are unaffected.
At this time, the exchange is completely unavailable. Users can check the Bitfinex Status page for updates as well. This story is developing and as soon as there are more details, we will provide an update.
In June, the exchange platform was down for a long period of time due to datacenter issues, which were later resolved. They were also fined by the CFTC $75K for illegal off-exchange financial transactions.
The exchange is one of the most high volume platforms on the market, moving upwards of ~40,000 BTC per day.
Update: Bitfinex has confirmed that $61.8 million has been stolen from the exchange.