Japanese authorities now report that about 6:14 a.m. (Tokyo) Tuesday, March 15, there was an explosion at the Daiichi Unit 2 of the Fukushima Nuclear Station. This explosion was heard, not seen from the outside. The explosion reportedly did not blow off the roof/walls, as the explosions did at Units 1 and 3.

Japanese responders continue to battle rising heat and pressure and falling water levels in the damaged reactors, Units 1 and 3, at Fukushima I (Daiichi) Nuclear Power Station.

In the aftermath of the devastating earthquakes and tsunami that struck Japan, we’ve been trying to piece together the status of the nuclear station at Fukushima. There are six units there, and units 1 and 2 appear to be at risk.