Typically they vent when they burn so I wonder what the hell happened. There would have to be some additional monkey business to get one to explode.

Aggh. Fucking image uploader. I've got better photos but am headed out of town for a few days. I'll figure it out when I get back. Cali plates on...

Or a small bomb was used to blow up some big bombs that were sitting the the buildings or on the planes.