VATICAN CITY (AP) — White smoke poured from the chimney of the Sistine Chapel and the great bells of St Peter's Basilica tolled Thursday after cardinals elected the 267th pope to lead the Catholic Church on the second day of their conclave.

The crowd in St Peter's Square erupted in cheers, priests made the sign of the cross and nuns wept as the crowd shouted "Viva il papa!" after the white smoke wafted into the late afternoon sky at 6.07pm. Waving flags from around the world, tens of thousands of people waited to learn who had won.

The smoke signal means the winner secured at least 89 votes of the 133 cardinals participating in the conclave to elect a successor to Pope Francis.

As the crowd waited, the Swiss Guards marched out and a military band played, marching up the steps to the basilica.

The name will be announced later, when a top cardinal utters the words "Habemus Papam!" — Latin for "We have a pope!" — from the loggia of the basilica. The cardinal then reads the winner's birth name in Latin and reveals the name he has chosen to be called.

The new pope is then expected to make his first public appearance and impart a blessing from the same loggia.