japan. i'm wolf blitzer, you're in "the i'm wolf blitzer, you're in "the situation room." -- captions by vitac -- www.vitac.com let's beginning with the breaking news right now at that nuclear power plant, a state of emergency is in effect for three reactors at these nuclear power facilities, the same place where an explosion today injured four people. as we said, there are conflicting reports about a meltdown in one of the reactors. a meltdown is a catastrophic failure of the reactor core with a polish for a widespread release of radiation. cnn's anna coren is in sendai, a port city closest to the quake's epicenter. a city of about 1 million people, it was devastated, though, by the tsunami. anna is joining us now. anna, tell us about these two most recent aftershocks that you've just experienced. >> reporter: wolf, we have