Earthquake hits Tokyo

First-hand blog reporting! We just had a huge earthquake here in Tokyo. It hit just now while I was at my computer. I'm fine, and there was no damage to my house, but it was the biggest one I've felt, ever. I wouldn't be surprised to hear that elsewhere in Japan there were injuries and significant damage. Another aftershock is rocking my monitor as I type this sentence.

FOLLOW-UP:
Here are some early MSM reports: (1), (2), (3), (4). Apparently it was a magnitude 5.7 quake (on the Richter scale, not the Japanese scale) with its epicenter in Chiba prefecture. No risk of a follow-on tsunami is seen, but Narita airport shut down its runways to check for damage.

ANOTHER FOLLOW-UP:
Bloomberg News now says it was a 6.1 magnitude quake. It also notes that commuter trains and subways throughout Tokyo were stopped when the quake hit, while shinkansen "bullet train" operations were suspended. And after checking for damage, Narita airport has re-opened its runways.