UN investigators are increasingly certain Pakistani leaders knew the country's top atomic scientist was supplying nuclear technology and designs to other nations, particularly North Korea, according to diplomats familiar with a probe of the world's nuclear black market.
While rogue nations were the main customers of the black market, sales of enriched uranium and warhead drawings have fed international fears that terrorists also could have bought weapons technology or material, the diplomats said in a series of interviews.
The investigation has widened beyond Iran, Libya and North Korea -- the identified customers of the network headed by Abdul Qadeer Khan -- the diplomats said, speaking on condition of anonymity.
The diplomats' assessment comes about half way through the probe by the International Atomic Energy Agency and Western intelligence services into the Khan network, whose tentacles extended from Pakistan to Dubai, Malaysia, South Korea, Switzerland, Germany, Japan, Britain, the Netherlands and beyond with potential ties to Syria, Turkey and Spain.
Investigators said they expect to complete the probe by June, eight months after US officials confronted the Pakistani government with suspicions about Khan, setting into motion events that led the father of Islamabad's nuclear program to confess last month.
Despite denials by the Pakistani government, investigators now are certain that some, if not all, of the country's decision makers were aware of Khan's dealings, especially with North Korea, which apparently helped Islamabad build missiles in exchange for help with its nuclear arms program, said one of the diplomats.
"In Pakistan, it's hard to believe all this happened under their noses and nobody knew about it," he said.
The diplomats didn't say which parts of the Pakistani government might have know of Khan's black market activity -- military, political or both.
But Andrew Koch, of Jane's Defense Weekly, said he ran into evidence that senior military officers knew of Khan's sideline four years ago when he attended a military technology exhibition in Karachi. There, the booth of A.Q. Khan's Research Laboratories, complete with pamphlets offering uranium enrichment equipment, shared space with displays of electronics, anti-tank missiles and other items being sold by the government defense industry, he said.
"I picked up the [Khan] brochures and I inquired whether everything inside was for sale and was told, `yes, of course, it all had government approval and was available for sale and export,'" he said from Washington.
Pakistani President Pervez Musharraf has insisted his government was not involved.
"The Pakistani government has never and will never proliferate," he told a meeting of world leaders in January in Davos, Switzerland, pledging to prosecute all "anti-state" elements found culpable.
But his pardon of Khan led to speculation the scientist agreed to keep silent on any government involvement.
Much of the goods involved were expensive and high-tech uranium enrichment centrifuge components sold to Libya -- which has confessed to trying to build weapons of mass destruction -- and to Iran, which denies such ambitions and says its enrichment plans are not for warheads but nuclear power.
Such equipment would be useless to terrorists lacking the space and expertise needed to set up thousands of centrifuges in series and repeatedly recycle isotopes until they were weapons grade. The tens of millions of dollars needed to buy the equipment might also be a deterrent.