_ WORKERS STOP RADIOACTIVE LEAK. After several days of failed attempts, workers halt a leak of highly radioactive water into the ocean that had raised concerns about the safety of seafood. But officials do not rule out the chance of contaminated water still leaking into the sea from other points.
_ ENGINEERS PREPARE TO INJECT NITROGEN. In a sign the reactors are still far from stabilized, engineers prepare to inject nitrogen into containment vessels around the cores to deter any hydrogen explosions. Nitrogen can prevent hydrogen from exploding _ as it did three times in the first few days after the plant's cooling systems were crippled by the 9.0-magnitude earthquake and tsunami on March 11.
_ PUMPING OF CONTAMINATED WATER ALMOST COMPLETE. Workers nearly finish pumping 3 million gallons of less contaminated water into the sea to make room in a warehouse for more highly radioactive water that has pooled around the plant, impeding workers' progress in restoring normal cooling systems.
_ TOYOTA WARNED OF POSSIBLE DOWNGRADE. Moody's Investors Service warns it may downgrade its credit rating for Toyota Motor Corp. due to the financial fallout from suspended car production following the quake and tsunami. The automaker's stock price has fallen nearly 10 percent since March 11.