Did massacre gunman make internet threat the day before Sandy Hook massacre? (DM)

It's from Daily Mail, but they have a screen cap of the chat transcript, so I thought I'd post this:

http://www.dailymail.co.uk/news/article-2248869/Adam-Lanza-Did-massacre-gunman-make-internet-threat-day-Sandy-Hook-massacre.html

The screencap at the link has a pixellated graphic of the Columbine shooters (dead) attached, so I don't want to post it here. But the chat capture basically says that he is going to kill himself, watch for the news, and that he's from Connecticut - with the attached photo.

EDIT:

It appears it WAS posted at 4chan and has since been removed.
If you use google and search for iKTatjYX
http://www.google.com/search?client=safari&rls=en&q=iKTatjYX&ie=UTF-8&oe=UTF-8
The search results show a 4chan page labeled 8293098 - /pol/ - Politically Incorrect
If you click it goes to a 404 page - but if you mouse over the arrows on the right of the listing above - it pops up the cached screencap of the unpixelated image