User blog comment:Xilinoc/Ch. 546 - THE LAST 9DAYS/@comment-5657895-20130717152442/@comment-5695542-20130717214438

Aizen was in the Sereitei in a prison under the 1st division (Yamaoto's group) and Ywhach or whatever his name is went to see him about joining the Vandenreich but turned him down and was killed for it. Or at least he was at the heart of a blast that destoried the 1st division's barracks and Ywhach said he now has eternity to think about it. Said here http://www.mangastream.to/bleach-chapter-524-page-13.html

Blast that destoried the 1st division barracks here. http://www.mangastream.to/bleach-chapter-524-page-8.html