Japanese officials are conceding the core of a damaged reactor at the Fukushima Daiichi nuclear power station may have cracked. Nuclear safety officials say a probe is underway to determine the source of the leak that has emitted dangerous levels of radiation and raised fears of contaminated food and water supplies. Two workers at the plant were hospitalized on Thursday after stepping in contaminated water. The water had 10,000 times the amount of radiation normally found in water from a functioning reactor. The official death toll from the Japanese earthquake and tsunami has passed 10,000, with more than 17,000 missing.