The prosecutor of the International Criminal Court on Wednesday called for the arrest and surrender of Saif al-Islam Gaddafi, who is wanted on war crimes charges for allegedly suppressing opposition to the rule of his father, former Libya ruler Muammar Gaddafi.
On Sunday, Saif al-Islam's lawyer said his client had been released under an amnesty law passed by parliament from prison in the eastern Libyan town of Zintan, where he had been held since 2011.
ICC prosecutor Fatou Bensouda said in a statement that her office was trying to verify Gaddafi's release.
"I call on Libya and all other States, if in a position to do so, to immediately arrest and surrender Mr Gaddafi to the ICC," she said.
Saif, whose whereabouts are not known, was last seen by an independent international observer in June 2014.