Some sort of underground/manhole explosion happened across the street from TPM HQ about a half hour ago and basically took out a local Radio Shack.
(see more photos here.)
I do not have any official word. But I did not see any signs of people being treated for injuries.
At first glance it looked like the Radio Shack had been engulfed by flames and gutted. But when you looked closer, it looked like a lot of what had been inside that store remained more or less intact. And in addition to the smoke coming from the store there was smoke coming from a grate just in front of it. So it seems like what happened is that an explosion — reports suggest a transformer explosion — happened just under the shop, filled it or at least the front of the shop in flames and scorched 4 or 5 floors of the front of the building.
Late Update: New York magazine has an amazing picture of what the actual blast looked like.