They are knee-deep in the rubble. Digging out the debris will be essential before a cause can be pinpointed.

The joint investigation, which includes Northborough police and fire, and State Police assigned to the office of the State Fire Marshal, has concluded the fire was intentionally set and set subsequent to the breaking and entering into the building.

Investigators systematically rule out all possible causes until they are left with only one. They've not been able to come to a single cause determination.

The goal is to get everyone to voluntarily comply with the law.

It only takes a cup of gasoline to destroy a million gallons of drinking water.