Benedict processed down the central aisle of St. Peter's Basilica at the start of the Mass without incident; with his normal phalanx of bodyguards on either side, he stopped twice to bless babies held up to him from the pews.
As a brass ensemble played, the crowd snapped pictures and clapped as he made his way to the altar.
During the Christmas Eve service in 2008 and 2009, a mentally disturbed woman lunged at the pope as he processed down the aisle — and last year managed to pull him to the ground.
The Vatican identified her as Susanna Maiolo, a Swiss-Italian national with a history of psychiatric problems. Both years she wore a telltale red sweat shirt.
Security was also vigilant Friday due to the package bombings a day earlier at the Swiss and Chilean embassies, for which anarchists claimed responsibility. The two people who opened the envelopes were injured.
The bombings added to tensions in the capital following a violent, anti-government protest last week in the historic center and a fake bomb found Tuesday on a Rome subway.
