ISTANBUL, Turkey (AP) _ The gunman who shot Pope John Paul II was escorted amid heavy security Wednesday to a courthouse where he faced trial on robbery charges.

Snipers guarded rooftops, and armored personnel carriers were stationed around the Istanbul courthouse.

Wednesday's session was the third in the trial of Mehmet Ali Agca. In the Turkish criminal justice system, trials are often held in sessions of one day each month. Agca was last in court July 10.

He has rejected accusations that he was involved in the 1979 robberies of a soda plant and a jewelry store and the theft of a getaway car. Agca, who is already serving 10 years in prison for killing a liberal newspaper editor, faces between 15 and 30 more years in prison if convicted on the new charges.

Agca was extradited to Turkey in June after Italy pardoned him. He had served almost 20 years in prison for the 1981 shooting of the pope.

In a hearing last month for the robberies, Agca accused the Vatican of being the ``enemy of God and humanity'' and called on the pope to resign immediately.

Agca also issued a handwritten statement through his lawyer accusing the Vatican of orchestrating the 1981 assassination attempt against the pope.

Italian newspapers said the outburst was a calculated attempt to win favor with Turkish nationalists and fundamentalists in the hope of receiving some kind of clemency. A far-right party is the senior partner in Turkey's governing coalition.

Agca is thought to have been close to an ultranationalist group, the Gray Wolves. He is admired by some right-wing extremists, who consider him a patriot who fought leftists in Turkey.