The blast wave & the fire ball is travelling from the left side to the right side of the screen machan,as if someone behind the minister blew it up.If the guy whom u r suspecting blew himself up,Don't u think the blast wave would have travelled towards the camera & even killed the camera man??
cn nt b !!!! certainly nt
look at the other 2 images as well. The direction is towards the car so it can't be a bomb behind Mr.Jeyaraj.. It has to be some one in the marathon.