A bus in the Dutch city of Delft on fire, until the natural gas starts to leak from the tanks and it becomes a flame thrower. [video]http://www.omroepwest.nl/node/98417/overlay[/video]
You have any more info on that? Was it compressed gas, liquid propane, or something else? That "leak" was a from a blow off valve, designed to reduce the pressure in the vessel. It may seem violent (since the gas ignites on exit), but it's to prevent an even worse explosion.
Exactly a BLEVE explosion is something to avoid at all costs. Assuming it was liquid NG. Rupturing pressure vessels is also very very bad thing. This is the type of thing that turns me off of H2 and NG/LPG, as this is a 'safe' failure mode.
About four or five years ago, we had an acetylene manufacturing facility go up. I don't know if you see it in this video, but a bus simply melts to the ground and one of the tanks shot about 3/4 mile down I-35 and torpedoed into an overpass. Was very eventful.