U.S. Nuclear Regulatory Agency asked to help with damaged reactors
Japan fights to avert nuclear meltdown
Earthquake fallout in Japan prompts safety concerns in U.S.
Nuclear reactor on red alert
An inside look at the danger posed by the nuclear reactor problems caused Japan's earthquake
Former U.N. weapons inspector sheds light on dangerous situation in Japan
Food sources could be tainted too
Officials racing to prevent meltdown , radiation exposure
Search for survivors continues
Japan's nuclear crisis spikes demand for potassium iodide pills
Japanese officials are at odds over plan for Fukushima Dai-ichi nuclear plant
Shepard Smith reports from Tokyo
U.S. being overly cautious or realistic about nuclear radiation risk?
Will Japanese gain control of nuclear plant ?
Japanese crews work on power line to troubled plant
Some exposed to radiation
Need to restore power to water pumps
A look at fact versus fiction on nuclear reactor meltdown fears in Japan
What exactly is a nuclear meltdown ?
Japanese authorities order 140,000 people around plant to stay indoors