On August 2nd the Hong Kong-based Bitcoin exchange Bitfinex was compromised for roughly $70 million worth of Bitcoin. According to sources, the attacker managed to drain the exchange through its multi-signature security — gaining 120,000 BTC from the breach. Now the exchange is trying to reach out to the responsible party in an attempt to get its customers’ Bitcoin returned.
https://news.bitcoin.com/bitfinex-seeks-bitcoin-thief/