New Delhi/IBNS: Pakistan Supreme Court Thursday called Imran Khan's arrest by the country's top anti-corruption body 'illegal' and he should be released immediately amid violent protests by the former president's supporters.

Khan, who is facing corruption charges, is under the custody of the National Accountability Bureau (NAB).

The order to bring Khan to the Supreme Court was issued by a three-member bench of Chief Justice Umar Ata Bandial, Justice Muhammad Ali Mazhar, and Justice Athar Minallah.

After hearing Khan's request for relief, the country's apex court strongly criticised the NAB for arresting him from the Islamabad High Court's premises, where he had come to appear in a case.

The Supreme Court said Khan, who heads the Pakistan Tehreek-e-Insaf (PTI) party, should return to the Islamabad High Court at 10 am on Friday and follow whatever the high court decides.

Only 10 of his supporters will be allowed to meet him, the court said.

Imran Khan has alleged he was tortured in the NAB custody and was not allowed to even use the washroom. The former cricketing superstar alleged that he was given an injection to induce a slow heart attack.

His arrest comes after months of political crisis and at a time when the country's powerful military rebuked the former international cricketer for alleging that a senior officer had been involved in a plot to kill him.

Some of his protesters took out their wrath on the military, torching the residence of the corps commander in Lahore and laying siege at the entrance to the army's general headquarters in the garrison city of Rawalpindi.