Vatican City. Catholic cardinals on Wednesday performed a solemn ritual to transfer Pope Francis' body from his residence in the Vatican’s Santa Marta guesthouse to St. Peter’s Basilica, where the faithful will be able to pay their respects over three days of public viewing.

Cardinal Kevin Farrell, who is overseeing Vatican administration until a new pope is elected, led the ceremony in the chapel of the Domus Santa Marta hotel, where Francis had lived. A choir sang as cardinals in red cassocks and capes stood in prayer. The pope’s casket, flanked by four Swiss Guards standing at attention, was readied for procession.

Outside, priests holding long candles and accompanied by Swiss Guards waited to lead the way into the basilica. Crowds of mourners filled St. Peter’s Square to witness the moment.

Heads of state are expected to attend the funeral on Saturday in St. Peter’s Square, but the public viewing is largely for everyday Catholics to mourn the 88-year-old pope, who died Monday following a stroke.

Francis first lay in state privately at the Domus Santa Marta for Vatican residents and the papal household. Photos released Tuesday showed the pope in an open casket, wearing red papal robes and a bishop’s pointed mitre, his hands folded over a rosary. Cardinal Pietro Parolin, the Vatican’s secretary of state, was seen praying at his side.

Beginning Wednesday morning, the public can view the body inside the basilica, which will remain open until midnight on Wednesday and Thursday. The viewing period will end Friday at 7 p.m.

In a break from tradition, Francis’ casket will not rest on an elevated bier but instead will lie directly on the main altar, facing the pews.

Italian authorities have tightened security around the Vatican, deploying foot and mounted police as pilgrims continue to arrive for the Holy Year events that Francis launched in December. Pilgrims who pass through St. Peter’s Holy Door during the Jubilee year receive indulgences,  a remission of temporal punishment for sins.

The funeral is scheduled for 10 a.m. Saturday in St. Peter’s Square, with attendees expected to include U.S. President Donald Trump and Ukrainian President Volodymyr Zelenskyy.

Meanwhile, cardinals continue their meetings this week to prepare for the conclave that will elect Francis’ successor and to manage other Church affairs.