ISLAMABAD, July 25: Three senior officials of the Khan Research Laboratories (KRL), who were released on Saturday, are reported to have been asked by the authorities to remain quiet about their 'debriefing' sessions and not to disclose any information about their departments.

The three officials, Dr Mohammad Nazir, Director-General of Science and Technology, Brigadier (retd) Sajawal Khan, Director-General of Maintenance and Construction Division, and Major (retd) Islamul Haq, Personnel Staff Officer to Dr Abdul Qadeer Khan, signed an undertaking that they would not leak any information.

The officials have also been directed to avoid contacting any foreign government, authority, corporation or person without obtaining prior permission from the federal government. They are also required to inform the KRL's director-general of security prior to leaving Islamabad.

The release of the officials was surprising even for their families as the Federal Review Board (FRB) comprising three senior judges of the Supreme Court had recently extended their detention for another 90 days, sources close to the officials told Dawn. The last meeting of the FRB which decided to release the officials was held on July 23.