In the 1980s, Pakistani ISI Director Akhtar Abdur Rahman was supervising a secret trade in which CIA weapons meant to go to mujaheddin fighting the Soviets in Afghanistan were sold to others by the ISI. The profits were then used to fund the Kahuta Research Laboratories, which A. Q. Khan was using to develop a Pakistani nuclear bomb (see 1980s). To disguise where the weapons were coming from, the CIA bought Soviet-made weapons on the black market and then shipped them to the ISI. The ISI stored them at an arms depot in Ojiri, near the town of Rawalpindi. By 1988, the US finally demands an independent audit of the depot, after persistent reports of corruption. On April 10, 1988, several weeks before US inspectors are to arrive, the arms depot blows up. The explosion is so massive that it kills 100 and injures over 1,000. The Pakistani government will officially determine the explosion was an accident. However, Hamid Gul, who became ISI director in 1987 (see April 1987), will conduct a secret audit for the ISI about the explosion and confirm that it was caused by sabotage to hide the massive theft of munitions. The US ambassador to Pakistan will estimate that about $125 million worth of explosives are destroyed in the blast. [Levy and Scott-Clark, 2007, pp. 131-132]