Earlier today, certain realms were affected by an in-game exploit, resulting in the deaths of player characters and non-player characters in some of the major cities. This exploit has already been hotfixed, so it should not be repeatable. It's safe to continue playing and adventuring in major cities and elsewhere in Azeroth.
Who has the same problem?
More information bugfix and some video with the problem click here
Edited, Oct 8th 2012 1:05pm by Darqflame Lock Thread: Dupe Subject