AFTER DAYS OF informal talks, the formal process of electing a new leader for the Roman Catholic Church began this afternoon in the Sistine Chapel in Vatican City.

115 cardinals from around the world were locked in to the 15th century church to begin the process – which is expected to last days – after attending a special mass in St Peter’s Basilica.

These photographs were taken before and during the mass.

Cardinal Timothy Dalton (right) waves to reporters this morning before leaving on a bus to go to the Vatican’s Domus Sanctae Martae, the hotel where the cardinals stay during the conclave. (AP Photo/Alessandra Tarantino)

A pilgrim with bare feet and wearing a sackcloth kneels in St Peter’s Square during the mass at the Basilica before the cardinals sequestered themselves in the Sistine Chapel. (AP Photo/Michael Sohn)

Photographers shoot photos of friars as they cross St Peter’s Square (AP Photo/Michael Sohn)

Italian cardianl Angelo Scola arrives at the mass inside St Peter’s Basilica (AP Photo/Andrew Medichini)

Cardinals enter the mass at St Peter’s Basilica (AP Photo/Andrew Medichini)

(AP Photo/Andrew Medichini)

(AP Photo/Andrew Medichini)

(AP Photo/Andrew Medichini)

(AP Photo/Andrew Medichini)

A nun follows the proceedings of the mass on a giant screen in St Peter’s Square (AP Photo/Emilio Morenatti)

(AP Photo/Andrew Medichini)

(AP Photo/Andrew Medichini)

People watch the mass on giant screens in St Peter’s Square (AP Photo/Emilio Morenatti)

Portuguese cardinal Jose Saraiva Martins in St Peter’s Square (AP Photo/Emilio Morenatti)

Read: Centuries-old rituals to be carried out as conclave begins >

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