From the Guardian:
The rest of the article is at: http://tinyurl.com/7sl6l
I guess it had nothing to do with his investigation into the misuse and misappropriation of funds by the US and UK in Iraq.
Quite how his 3 year old daughter and seven month son reacted to having the bedroom sprayed with bullets is not clear in the article.
What the article does make clear however, is that Dr. Ali Fadhil was quickly released, but the tapes of the program he was making about the misuse of funds were not released.