People stand on the roof of an elementary school in Sendai, northern Japan as they take shelter Saturday, March 12, 2011 after Japan's biggest recorded earthquake slammed into its eastern coast Friday.
PICTURES: Tsunami reactions around the world
PICTURES: Search and rescue in JapanPICTURES: World's biggest tsunamis
PICTURES: How earthquakes are measured
PICTURES: Deadliest earthquakes
Credit: AP Photo/Kyodo News