Pakistan said earlier this month that the probe into the Khan matter was closed and that he would remain off limits to foreign investigations despite requests by the United States and the global nuclear watchdog agency IAEA to interview him.

While President George W. Bush's administration has said that Pakistan had taken all actions necessary to unravel the network and to uncover all of its secrets, lawmakers are unconvinced.

"We have given Pakistan a get-out-of-jail-free card on the single worst case of profileration in the past 50 years," Democratic Representative Gary Ackerman told a House of Representatives hearing Thursday on Khan's smuggling ring.

Ackerman and several other lawmakers pushed Washington to pressure Pakistani President Pervez Musharraf, a key ally in the US "war on terror," to get to the bottom of the issue.

Given the "grave consequences" of Khan's acts and "his relevancy" to the current Iranian and North Korean crises, the US and the international community should expect more from Musharraf, said Republican legislator Ed Royce, who chaired the hearing by a House panel dealing with international terrorism and nonproliferation.

"Some question whether the A Q Khan network is truly out of business, asking if it's not merely hibernating. "We'd be foolish to rule out that chilling possibility," Royce said.

"Vigilance and greater international pressure on Pakistan to air out the Khan network is in order," he said.

David Albright, an American nuclear expert, told the hearing that the Khan case "is far from closed."

"Many questions remain about what Khan and his associates supplied other countries, particularly Iran," he said.

Specific questions involving Iran include the extent of uranium-enriching centrifuge assistance, the logistics of that assistance and the possible supply of nuclear weapon designs, he said.

"These areas remain especially troubling as we try to determine exactly how close Iran could be to building nuclear weapons and what sensitive information may remain in circulation around the world that could fall into the hands of other enemies of the United States, including terrorists," he said.

Leonard Weiss, a former staff director of the US Senate governmental affairs committee, told the hearing that Khan began bringing Iranian scientists to Pakistan as early as 1988 for training in technology that could accelerate its controversial uranium enrichment program.

Iran is currently under pressure to halt its nuclear energy drive, seen in the West as a mask for weapons development. The United States is pushing for UN sanctions to force the Iranians to halt their uranium enrichment activities.

Khan, currently under house arrest after being pardoned by Musharraf, has not been questioned by any non-Pakistani investigators and reportedly only answered a limited number of questions from foreign investigators, the hearing was told.

"It is safe to assume that critical questions regarding the nuclear programs of Iran and North Korea, and possibly other countries, go unanswered," said Democratic Representative Brad Sherman.

"This was by all accounts a massive network, but Pakistan has only focused on Khan and about a dozen associates. The last of these to be held in detention was recently released. None were prosecuted," he noted.

Aside from Iran and North Korea, Khan also reportedly sold nuclear equipment or technology to Libya and Syria.

Some information has been passed from Musharraf to the United States based on Pakistani debriefings of Khan, but neither Islamabad nor the Bush administration have made any public statements about what Khan may have said.

Khan and his associates had reportedly visited Chad, Egypt, Mali, Niger, Nigeria, Sudan, Saudi Arabia and Syria.

Related Links