Eurogamer said:Eurogamer has received multiple reports of Diablo 3 accounts being hacked.
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The reports coincided with the EU Diablo 3 servers going offline on Sunday afternoon for around four hours, preventing players from logging in (error 33). It has been suggested that the EU servers were taken offline following a SQL injection attack, but this remains unconfirmed.
I just took a quick glance at the OT and it seems people on there were affected as well.
Reports are coming that people had their B.Net accounts logged in at the time of the hack.
Eurogamer's own Christian Donlan had his account hacked:
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