U.S. raises alarm over Japan nuclear crisis

There is no water in the spent fuel pool and we believe that radiation levels are extremely high, which could possibly impact the ability to take corrective measures,' he said.
Japanese officials denied that all the cooling water was gone.

Hajime Motojuku, spokesman for plant operator Tokyo Electric Power Co., said the 'condition is stable' at Unit 4.

If Jaczko is correct, it would mean there's nothing to stop the fuel rods from getting hotter and ultimately melting down. The outer shells of the rods could also ignite with enough force to propel the radioactive fuel inside over a wide area."

Source: MSNBC