Musharraf reiterated to a meeting of top officials that any scientist found guilty would be "severely" punished.

"A high-level meeting chaired by President Musharraf reviewed the whole case in the light of information received from the International Atomic Energy Agency (IAEA) about Iran and Libya," Information Minister Sheikh Rashid told a press conference.

"The meeting reiterated that those found guilty will be dealt with severely and those found innocent will be allowed to go home."

Earlier Musharraf told the BBC "we will punish them."

"And we will be very harsh with them because they are enemies of state and they have done something for personal and financial gain," he said in an interview.

About a dozen nuclear scientists and administrators, including the "father" of Pakistan's bomb Abdul Qadeer Khan, are under investigation for allegedly selling nuclear know-how to Iran, Libya and possibly other countries in the 1980s and 1990s.

Interrogations of the scientists have sent shockwaves through Pakistan, where nuclear experts are revered as national heroes for their contributions to making Pakistan a nuclear power. All except Khan have been detained.

The minister said seven people were still under investigation, four of them were associated with the security matters.

Four others were cleared by the investigators. "One or two more are expected to be released shortly while the whole process of investigation is likely to be over by the end of this month, Rashid said.

The purpose of the probe is "not to disgrace the scientists. We accord our scientists full respect," Rashid said, adding that those undergoing debriefing have not been arrested. "There are no restrictions on doctor Qadeer Khan."

The independent Human Rights Commission urged transparency in the secretive probe and said the detainees should be produced in court.

"It must be noted that transparency can help remove many doubts about the nature of the action taken," it said in a statement.

The government probe, under way since December, was prompted by information from the IAEA and subsequent trips by Pakistani investigators to Iran, Libya and IAEA headquarters in Vienna.

Musharraf told the BBC "some unscrupulous individuals" may have taken advantage of the autonomy given to A.Q. Khan Research Laboratories (KRL), Pakistan's key uranium enrichment facility, in the late 1980s and 1990s as it helped develop Pakistan's nuclear program.

"Within that ambit of that autonomy and security some unscrupulous individuals may have gotten involved," he told the BBC.

He said they could have acted "unilaterally, without the knowledge" of then governments or military chiefs, rejecting reports that have named a former military chief, General Aslam Beg, as approving the transfer of nuclear technology to Iran under the former governments of Prime Ministers Benazir Bhutto and Nawaz Sharif.

Musharraf and other officials have repeatedly said that no government or military institutions were involved in sharing nuclear techonology and know-how.

But observers are sceptical that such strategic security information could have been passed overseas without higher approval.

"The transfer of such materials is impossible without explicit permission from the security apparatus that constantly surrounds the nuclear establishment, installations and personnel," Pervez Hoodbhoy, professor of physics at Islamabad's Quaid-e-Azam University, told AFP.

"It would've been impossible without explicit permission from the highest levels of those in charge of security."

Musharraf in several weekend remarks pointed to an international black market of nuclear technology traders, fuming that only Pakistan has been under the media's spotlight.

"What about the individuals in Europe? And I know that there has been found in Europe (people) involved in the fabrication of the equipment, and that needs very high technology," he told the BBC.

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