"Smiling Buddha", Ministry of External Affairs (MEA) was the assigned code name of India's first successful nuclear bomb test on 18 May 1974. The bomb was detonated on the army base Pokhran Test Range (PTR), in Rajasthan, by the Indian Army under the supervision of several key Indian generals. The device was formally called the "Peaceful Nuclear Explosive".

The device was detonated on Buddha Jayanti (a festival day in India marking the birth of Gautama Buddha). Indira Gandhi maintained tight control of all aspects of the preparations of the "Smiling Buddha" test, which was conducted in extreme secrecy; besides Gandhi, only advisers Parmeshwar Haksar and Durga Dhar were kept informed. Scholar Raj Chengappa asserts the Indian Defence Minister Jagjivan Ram was not provided with any knowledge of this test and came to learn of it only after it was conducted. Swaran Singh, the Minister of External Affairs, was given 48 hours advance notice. The Indira Gandhi administration employed no more than 75 civilian scientists while General G. G. Bewoor, Indian army chief, and the commander of Indian Western Command were the only military commanders kept informed.

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