Vatican City ? Pope John Paul II ushered in the Christmas holiday early Thursday in a midnight Mass in St. Peter’s Basilica, decrying that “too much blood is still being shed” in conflicts around the world.

The 83-year-old pope, who suffers from Parkinson’s disease, cut back his holiday activities only slightly, insisting on celebrating the Mass in the packed basilica decorated with red poinsettias.

After lighting a candle for peace, the pontiff delivered his entire homily, speaking slowly but in a clear voice.

In recent weeks, amid reports that churches could become terrorist targets, security has been tightened around the Vatican. Italian police guarded the perimeter of the vast St. Peter’s Square and pilgrims entering the basilica passed through metal detectors.

In his homily, the pope decried, “Too much blood is still being shed on earth. Too much violence and too many conflicts trouble the peaceful coexistence of nations.”

“You come to bring us peace,” John Paul said of the baby Jesus. “You are our peace.”

Pilgrims from many countries attended the Mass, with the Church’s diversity underlined by the selection of children who presented the pope with flowers — 12 youngsters from Africa, Asia, Latin America and Europe, including two from John Paul’s native Poland.

Waiting for the Mass to begin, some in the crowd sat silently, some prayed and some snapped photos as John Paul was wheeled in by aides.

At noontime today, he will deliver his usual holiday “Urbi et Orbi” message — Latin for “To the City and the World” — and Christmas greetings in various languages.

Pope John Paul II blesses Giorgia Gnazi of Italy during the blessing of 12 children from different countries. The pontiff blessed teh children and delivered a homily at midnight Mass early today in St. Peter's Basilica at the Vatican.