By Syed Shoaib Hasan
BBC News, Islamabad
The Supreme Court of Pakistan has ordered the attorney general to trace the whereabouts of "missing people" within 15 days.
Chief Justice Chaudhry was reinstated after suspension
The court, headed by recently reinstated Chief Justice Iftikhar Chaudhry, was hearing petitions filed by relatives.
Hundreds of people have gone missing in Pakistan since 2001.
Rights groups say they are illegally detained by security agencies for alleged links with radical groups.
At a hearing on Monday, Chief Justice Chaudhry told Attorney General Malik Qayuum he had 15 days to find out where the people were.
Mr Qayuum had asked for time to come back with details on the matter.
Human rights organisations and the families of the missing say the state is still not willing to come clean on the issue.
"With the return of the chief justice, we are now much more hopeful," Amina Janjua of the Defence of Human Rights organisation told the BBC.
Mr Chaudhry was suspended by President Pervez Musharraf in March on allegations of corruption but was reinstated after a huge protest campaign.
Mrs Janjua said: "The government must not be allowed any more time... it is just prolonging our agony."
She has been personally affected - her husband, Masood, has been missing since 30 July 2005.
Defence of Human Rights has been campaigning for him and many others to be released.
Its activities have drawn the anger of the authorities, with its chief coordinator, Khalid Khwaja, currently behind bars.
Mr Khwaja has been campaigning for the missing for the past four years.
He is charged with aiding and abetting militants at Islamabad's Red Mosque, which the army stormed last month. Mr Khwaja says the charges are "false".
Currently, the court petition contains the names of 289 people who have gone missing over the past five years.
Their whereabouts are still unknown, although their families allege they are in state custody.