Two Underground Explosions Rock Chinatown/North Beach [Updated]

We're getting reports of a manhole explosion in the last hour near the corner of Grant and Pine, and PG&E is reportedly already on the scene. Emergency In SF reports that there were two underground explosions. Streets in the vicinity have already been blocked off to vehicle and foot traffic, and we don't yet know if there were any injuries.

And just when we were starting to get complacent again about living in a city where manhole tops didn't go shooting into the sky at any given moment! The last explosion we can recall was in September at Folsom and Harriet, but 2011 was relatively quiet, explosion-wise, compared to 2009-2010.

Update: The Chron is reporting that this was just a "small blast" and that the manhole cover was dislodged but "remained in its casing," and no one was injured. The streets were blocked off for an hour while fire officials investigated. The cause, says PG&E, was an underground equipment malfunction. Yeah, not that reassuring. [Chron]