Visitors pay their respects at Pope Francis' tomb

Roman Catholic faithful began visiting the tomb of Pope Francis on Sunday, filing past the simple white tomb in St. Mary Major Basilica a day after he was bade farewell by the powerful of the world and a crowd of hundreds of thousands.

A single white rose was placed on the tomb that said “Franciscus" — the pope's name in Latin.

A light cast its warm glow over the tomb and a reproduction of the late pontiff's pectoral cross on the wall above it.

People filed past, many crossing themselves or snapping photos with their phones.

Ushers urged them to keep moving to accommodate the thousands who flocked to the Rome basilica to see the tomb, forming a long line outside.

The tomb was opened on the second of nine days of official mourning for Francis, after which a conclave will be held to elect the next pope.

Meanwhile, a special Mass was held in St. Peter's Square led by Cardinal Pietro Parolin, the Vatican's secretary of state.

Parolin is considered a possible contender to be the next pope due to his prominence in the Catholic hierarchy.

No date has yet been set for the conclave, but it must start by May 10.

Cardinals who traveled to Rome for Francis' funeral will be meeting regularly this week ahead of the conclave as they start to chart a way forward for the 1.4 billion-strong Catholic Church.

Pope Francis chose his place of burial in St. Mary Major Basilica, near an icon of the Madonna that he revered, because it reflects his “humble, simple and essential" life, the archbishop who administers the basilica said Friday.