Japan's quake toll set to exceed 1,000

A devastating tsunami triggered by the biggest earthquake on record in Japan looked set to kill at least 1,000 people along the northeastern coast on Friday after a wall of water swept away everything in its path.

The government warned there could be a small radiation leak from a nuclear reactor whose cooling system was knocked out by the quake. About 3,000 residents in the area some 240 km (150 miles) north of Tokyo had been moved out of harm's way.

Underscoring grave concerns about the Fukushima plant, the U.S. air force delivered coolant to avert a rise in the temperature of its nuclear rods, but officials said a leak was still possible because pressure would have to be released.

The unfolding disaster in the wake of the 8.9 magnitude earthquake and 10-meter (33-feet) high tsunami prompted offers of search and rescue help from 45 countries.