Nearly a month after a 9.0-magnitude earthquake generated the tsunami along Japan's northeastern coast, more than 14,700 people are still missing. Many of those may have been washed out to sea and will never be found.

In the days just after the March 11 disaster, searchers gingerly picked through mountains of tangled debris, hoping to find survivors. Heavier machinery has since been called in, but unpredictable tides of radiation from the Fukushima Dai-ichi nuclear complex have slowed progress and often forced authorities to abandon the search, especially within a 12-mile (20-kilometer) evacuation zone around the plant.

Officials now say there's not much time left to find and identify the dead, and are ramping up those efforts.

"We have to find bodies now as they are decomposing," said Ryoichi Tsunoda, a police spokesman in Fukushima prefecture, where the plant is located. "This is a race against time and against the threat of nuclear radiation."

AP