The two in the space of 4 days were definately both fridgies, and accetylene the cause. There was also another incident in Melbourne just over 2yrs ago involving a plumbers van. The central locking remote set the explosion off.

http://youtu.be/qowfzBCmHsY

Fortunately he was far enough away from the van when it exploded and was uninjured

The guy at BOC told me the other day it was $40000 fine if caught carrying accetylene without it being vented through the floor