Pakistan's Supreme Court has ruled that the Inter Services Intelligence is not a law enforcement agency or a customs authority and cannot take anyone into custody under the country's laws.

A full bench of the apex court headed by Chief Justice Iftikhar M Chaudhry gave the ruling on Tuesday while hearing the case of a Pakistan-born German national Aleem Nasir, who was held by the ISI on charges of smuggling precious stones, The News reported in Islamabad on Wednesday.

The Supreme Court ordered the immediate release of Nasir and directed that all his travel documents, including passport seized by the ISI, should be provided to him so that he could return to Germany [Images].

"Under which law, Aleem was taken into custody by the agency?" the chief justice questioned.

Nasir, who was produced before the court, told the bench that he was arrested by the ISI from Lahore [Images] airport last month while on his way to Germany and subsequently taken to the ISI headquarters in Islamabad for interrogation.

He claimed that he was even threatened of handover to the United States.

The chief justice also ordered the release of another detainee Hafiz Abdul Basit who had been held captive by the security agencies for his alleged involvement in a planned attack on President Pervez Musharraf [Images] in 2004.

Attorney General Malik Muhammad Qayyum submitted before the court that Basit was in the custody of the political agent of the Khyber agency and assured that efforts would be made to bring him to the capital as soon as possible and that he would be released.

While hearing Basit's case on Monday, the court had directed the director general of Federal Investigation Agency to produce him before it the next day or face jail.

In another case, the bench ordered that Imran Munir, detained on charges of spying, be given into civil custody by the military and admitted to hospital for two weeks.

The court further directed that his family members and lawyers should be allowed to meet him any time.

The chief justice strictly directed the inspector general of police in Islamabad that Munir should not be handed over to any secret agency and he should personally take care of him. Munir was produced before the court on Tuesday, the daily reported.

Asma Jehangir, the chairwoman of the Human Rights Commission of Pakistan, had earlier said that Munir, a dentist by profession, was married to an Indian woman in Malaysia but had matrimonial relations with the niece of Brigadier Mansoor.

"This is a case of illegal detention," she had told the court.