The death toll has risen to 101.. Number of injuried is around 245.
I managed to find another photo of the moments before the suicide bombing (this one from the London-based Arabic daily Al-Shariq Al-Awsat) taken from KurdSat.
According to this Debkafile report, the Turkish Intelligence Services are behind the attack in an attempt to wipe out the entire Kurdish political and military leadership.
I can not confirm this (as most of Debka reports are wrong). I suspect Islamic fanatics.. probably Ansar Al-Shaytan (Islam) or Al-Qaeda. But hey, Turkish Intelligence services have been working in the area for long (undercover).
A photo of terrorist who blew himself up was released by the Kurdish police. He apparently looks like this :