The conclave to elect a new pope has officially begun, with a Vatican official calling out ''extra omnes'' and the door to the Sistine Chapel shutting.

The 133 cardinals from 70 countries will be locked inside the Sistine Chapel, where they will vote in secret and silence, a process designed to be both contemplative and free from outside

The smoke billowed out at 9 p.m. Wednesday, some four hours after 133 cardinals solemnly entered the Sistine Chapel, took their oaths of secrecy and formally opened the centuries-old ritual.