Pope Francis tours St Peter's Square in open vehicle to greet crowd before mass

Pope Francis toured a crammed St. Peter's Square in an open white jeep on Tuesday to greet a huge crowd gathered for a Mass to inaugurate his papacy, which has already fanned hope for a renewal of the scandal-plagued Roman Catholic Church.

In another sign of the informality that is already a mark of his papacy, Francis abandoned the bullet-proof popemobile frequently used by his more formal predecessor Benedict, to tour the sprawling square in bright sunshine.

Crowds had been pouring into the square and surrounding streets since before dawn. Francis, who was elected by a secret conclave of cardinals last Wednesday, stopped frequently to greet the crowd and kiss babies held up to him. He got out of the vehicle at one point to bless a disabled man.

The Mass, which was due to start at 9:30 am will formally install Francis as the new leader of the world's 1.2 billion Roman Catholics. The crowd may be the biggest in Rome since more than 1.5 million people came to the city for the beatification of the late Pope John Paul II on May 1, 2011.