Japan's fast-breeder nuclear reactor program has been controversial from the start.

The group's director, Steven Aftergood, said he obtained the report from sources in the reactor program.

The organization is a government-backed international coalition overseeing the reactor program.

To the Editor: I must respond to your Jan. 1 front-page article on the Navy's nuclear reactor program.

North Korea's nuclear reactor program, had it proceeded, would have produced enough weapons-grade plutonium to make several nuclear weapons a year.

Early in 1942, the reactor program was moved to the University of Chicago, where the first controlled chain reaction was achieved.

Some members of Congress and interest groups have raised particular concerns about the Energy Department's space-based reactor program.

"It's a dangerous game," he added, saying the move could backfire and cause a political storm that would endanger the reactor program.

After zirconium was chosen as material for nuclear reactor programs in the 1940s, a separation method had to be developed.

From the successful naval reactor program, plans were quickly developed for the use of reactor steam to drive turbines turning generators.