what happened to downed c-130?

I was wandering what was the final verdict of the crash investiagtion team who were finding out what downed the RAF hercules c-130 on the 29th of January just north of Baghdad? There were a couple of theories being thrown around by the press just after the tragic incident including it was shot down by a missile or several missiles at once to confuse onboard avoidance systems or that a bomb had been planted onboard which destroyed one of the wings. I never saw any official explanation and just wandered if i had missed it or whether the investiagtion is still going on?