bitcoin exchange hack

Bitfinex Team Investigates Security Breach, Releases Initial Relaunch Plan
August 4th, 2016

Bitfinex announced that all trading, deposits, and withdrawals will be temporarily disabled.

Chinese Exchange Bter Hacked as 7170 Bitcoin Stolen From Its Cold Wallet
February 15th, 2015

Popular Chinese Bitcoin exchange claimed that its exchange had been hacked, 7170 BTC valued at $1.66 million disappeared.