It's an old story. Mt.Gox was first hacked in 2011. The same year, the exchange Bitcoinica was destroyed by a theft hack.
Hell: Cryptsy - the biggest altcoin exchange of its time - was destroyed by a malware hack. There have been others.
It was so bad, I compared the "Wild West" to a Firefly world where the good guys were confined to horses and buggies and the bad guys flew away to the outer space of Internet anonymity.