The semiofficial Anatolia news agency suggested that Agca was expected to be immediately enlisted by the military for obligatory service because he had dodged the draft. However, it was not clear if that would happen because the military generally only accepts conscripts younger than 41.
Turkish paramilitary police were expected to take Agca first to a local military station and then to a military hospital in Istanbul for a medical check, a routine procedure.
Vatican spokesman Joaquin Navarro-Valls said the Vatican would defer to the judgment of the Turkish tribunal.
"The Holy See has learned only from news agencies of the news of the possible freedom of Ali Agca," he said in a brief statement. "The Holy See, before a problem of a judicial nature, submits to the decisions of the tribunals involved in this matter."
Agca's sister, Fatma Agca, said she also was surprised.
"We did not hear it," Fatma Agca told the AP from the family home in the southeastern city of Malatya.