BRASILIA, Brazil -- Brazil's new government has uncovered a 15-year-old secret military program to make an atomic bomb, the nation's top science official says.
The official, Jose Goldemberg, secretary of science and technology, said the project was started in 1975 under the presidency of Ernesto Geisel, an army general who is now a high official at the state petroleum company.
In early September, a 50-page classified report on the project reached Brazil's civilian president, Fernando Collor de Mello, who was inaugurated in March. Mr. Collor met with the heads of the army, navy and air force and told them he would stop the bomb project, Mr. Goldemberg said on Friday.
Although a Brazilian attempt to create an atomic bomb has long been widely rumored, successive Brazilian governments have firmly denied such a program existed. Brazil has never signed the international treaty intended to limit the spread of nuclear weapons. But ever since the Cuban missile crisis in 1962, experts in controlling nuclear proliferation have struggled to keep Latin America free of nuclear weapons.
"This is new -- I have never heard any official in Brazil confirm that there was an intention to make a bomb," said Gary Milhollin, director of the Wisconsin Project on Nuclear Arms Control, a private group that researches the spread of nuclear weapons.
On Sept. 18, in a first step to dismantle the bomb project, Mr. Collor flew photographers and officials to a previously off-limits air base in the Cachimbo mountain range of the remote central Amazon. As the heads of the three military services watched -- looking visibly ill at ease, according to the photographs -- the president threw a symbolic shovelful of cement into a hole four feet in diameter and 1,050 feet deep.
The pit, made of steel-reinforced cement, appeared to be designed for testing a nuclear explosive, said Mr. Goldemberg, a physicist who inspected the site with the president.
Brazilian physicists have concluded that the military was one or two years away from having the materials -- 20 to 35 pounds of weapons-grade enriched uranium -- to make a Hiroshima-type bomb. That, they say, was the only technical obstacle to creating the bomb when the project was stopped by Mr. Collor.
One week after symbolically sealing the test site, Mr. Collor traveled to New York, where he gave the strongest statement to date by a Brazilian president forswearing nuclear weapons.