Nuclear fission Mexico, which was the scientific hub for research on bomb development and design. Other sites, notably the Berkeley Radiation Laboratory and the Metallurgical Laboratory at the University of Chicago, played important contributing roles. Overall scientific direction of the project was managed by the physicist J. Robert Oppenheimer. In July 1945, the first atomic explosive device, dubbed "Trinity", was detonated in the New Mexico desert. It was fueled by plutonium created at Hanford. In August 1945, two more atomic devices – "Little Boy", a uranium-235 bomb, and "Fat Man", a plutonium bomb – were used against the Japanese cities of Hiroshima
Nuclear arms race test as a "peaceful nuclear explosion", but according to independent sources, it was actually part of an accelerated covert nuclear program of India. This test generated great concern and doubts in Pakistan, with fear it would be at the mercy of its long–time arch rival. Pakistan had its own covert atomic bomb projects in 1972 which extended over many years since the first Indian weapon was detonated. After the 1974 test, Pakistan's atomic bomb program picked up a great speed and accelerated its atomic project to successfully build its own atomic weapons program. In the last few decades of the