VATICAN CITY – Pope Benedict XVI implored the Syrian regime Sunday to heed international demands to end the bloodshed and expressed hope that the joy of Easter will comfort Christian communities suffering because of their faith.

Benedict, struggling with hoarseness and looking tired, celebrated Mass on Christianity’s most joyous holy day on the flower-adorned steps of St. Peter’s Basilica, before a crowd of faithful that swelled to more than 100,000 by the end of the 2-hour ceremony.

Only hours earlier the pontiff, who turns 85 on April 16, had led a long nighttime vigil service in the church. There have been concerns over his health, and he has recently used a cane in public appearances. He no longer walks down the basilica’s long aisle, traveling instead aboard a wheeled platform pushed by aides.

At the end of Sunday’s Mass, Benedict moved to the basilica’s central balcony to read his Easter message “to the entire world,” as he put it, delivering a ringing appeal for peace in Iraq, Syria and elsewhere in the Middle East, and in Africa, citing coup-struck Mali and Nigeria, where Christians and Muslims alike have been hit by terrorist attacks.