ROME - Under heightened security that included airport-style metal detectors at the gates of the Vatican, Pope John Paul II used his Easter message on Sunday to plead for the world to unite to overcome terrorism and "the logic of death."

The pope, speaking to tens of thousands of pilgrims in St. Peter's Square, prayed for leaders who are trying to resolve conflicts in Africa and the Middle East, including the Iraq war and Israeli-Palestinian violence. He called for what he described as the children of Abraham - Christians, Jews and Muslims - to rediscover their shared bonds.

The world, he said, needs to "find the strength to face the inhuman and unfortunately growing phenomenon of terrorism, which rejects life and brings anguish and uncertainty to the daily lives of so many hard-working and peaceful people."

The pope, who is 83, visibly frail and suffering from Parkinson's disease, has traditionally offered a message at Easter Mass that reflects upon world affairs. But this year, his comments came as Italy and the rest of Europe have grown increasingly anxious about the prospect of another terrorist attack.

On Sunday, hundreds of uniformed and plainclothes police officers patrolled St. Peter's Square, as well as nearby roofs and terraces.