This one is really off the charts:
My theories:
Accidental:
1) Nobody home (maybe on vacation) and problem develops with furnace or gas water heater. Fills house with natural gas during the day / night. Turns house into a bomb. Something sets it off - takes out house next door (probably the two deaths). Easy to confirm if we know the whereabouts of the occupants of the two homes (not reported yet by media as far as I know).Intentional causes:
2) Someone had an reason to kill the occupants of one of the homes. Drugs, bad debt, divorce/custody, love affair / adultery, etc.3) Collect on insurance, make it look like a faulty appliance, went overboard with the amount of natural gas leaked.
4) Owners unemployed, bank about to repo the house, owner decided to give the bank a smouldering crater instead.Anyone care to vote?
I vote for 4.
Regardless why or how it happened, I can't see anything other than a massive buildup of natural gas having enough energy to do this.