vowed never to allow a repeat. At the Multan meeting on 20 January 1972, Bhutto stated, "What Raziuddin Siddiqui, a Pakistani, contributed for the United States during the Manhattan Project, could also be done by scientists in Pakistan, for their own people." Siddiqui was a Pakistani theoretical physicist who, in the early 1940s, worked on both the British nuclear program and the Manhattan Project. In December 1972, Dr. Abdus Salam directed a secretly coded memo to Pakistani scientists working at the International Centre for Theoretical Physics (ICTP) in Italy to report to the Chairman of the Pakistan Atomic Energy Commission (PAEC), Munir Ahmad Khan, informing them about the program what was to be equivalent of the US "Manhattan Project." In an effort to instill a sense of pride, Salam noted that the heads of the Manhattan Engineer District were theoreticians, and informed the scientists at ICTP that a similar division was being established at PAEC; this marked the beginning of the "Theoretical Physics Group" (TPG). Other theoreticians at Quaid-e-Azam University would also join the TPG, then led by Salam who had done ground-breaking work for TPG. Among them was Riazuddin, Fayyazuddin, Masud Ahmad, and Faheem Hussain who were the cornerstone of the TPG. Tedious mathematical work on fast neutron calculations, relativity, complex hydrodynamics and quantum mechanics were conducted by the TPG led by Salam until 1974 when he left Pakistan in protest, though he kept close contact with TPG. No such endeavours of the kind had taken place in the country and computerized numerical control (CNC) and basic computing facilities were non-existent at that time (though later acquired). For this purpose, the calculations on the high-performance computing and numerical analysis were performed by Dr. Tufail Naseem, a PhD graduate in mathematics from Cambridge University, assisted by other members of Mathematics Division– the division of pure mathematics at PAEC under Dr. Raziuddin Siddiqui and Asghar Qadir. About the lack of CNC facilities, Munir Ahmad Khan famously marked: "If the Americans could do it without CNC machines in the 1940s, why can't we do the same now.". With Abdus Salam departing, Munir Ahmad eventually led the TPG and assisted in the calculations. Two types of weapon design were analyzed: the Gun-type fission weapon and the implosion nuclear weapon. The program turned to the more technically difficult implosion-type weapon design, contrary to the relatively simple 'gun-type' weapon. In 1974, Abdul Qadeer Khan a