I normally not jump at desaster news or such stuff.
But I happend to see live news about a incident in Lawrence, MA.
Appearently numerous houses suffered gas explosions and subsequently fires.
It has to be assumed that a lot of people got hurt from that.
However, before people start talking about terrorist attacks - I have seen something similar before.
In the late 70s or early 80s we had a similar situation, in a newly deveroped housing area outside a town. The cause was a overpressurization of the gas supply pipes. This caused ruptures and leaks all over the place, and about 30 houses exploded and/or burned down.
I hope the people there are getting instructed to do the right thing: air all parts of the house, including and especially the basement, to prevent a combustible mix to build up. And then pray...