The only information to accompany the announcement was a teaser image featuring the default Dovahkiin character with glowing yellow eyes.
Recent reports have suggested that the DLC will introduce Snow Elves and a Snow Elf Prince, as well as crossbows as a new weapon.
'Dawnguard' will be available on Xbox 360 this summer as a timed exclusive, with PC and PlayStation 3 versions expected at a later date.
Bethesda has also released today an update for the Xbox 360 version of Skyrim that adds Kinect support for over 200 voice commands. Commands include telling the game to save, commanding followers and using dragon shouts.
The Elder Scrolls V: Skyrim was released for PC, PlayStation 3 and Xbox 360 in November. It was named as the fastest-selling PC game on digital distribution service Steam.
Full details on the 'Dawnguard' DLC will be announced at E3 2012 in June.
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