World leaders have paid tribute to Pope Francis, who died on Monday aged 88, just a day after greeting delighted worshippers after Easter Mass.
The death of the Argentine pontiff, leader of the Catholic Church since March 2013, came less than a month after having been released from hospital following a 38-day battle with double pneumonia.
Some visitors to St Peter's Square - where a frail-looking Francis was cheered by Easter Sunday worshippers during an unscheduled appearance just a day earlier - were left in tears at the news.
Leaders of several nations spoke of the pope's moral and spiritual leadership while countries have begun preparations to mark his death.
"Dearest brothers and sisters, it is with deep sorrow that I must announce the death of our Holy Father Francis," said Cardinal Kevin Farrell in the statement published by the Vatican on its Telegram channel.
"This morning at 7:35 am (0535 GMT) the Bishop of Rome, Francis, returned to the home of the Father.
"His entire life was dedicated to the service of the Lord and His church," said the statement, released shortly before 10:00 am.
His death sets in motion centuries-old traditions that will culminate in the gathering of a conclave of cardinals to choose a successor.
In the next four to six days the Vatican's cardinals will decide on the pope's funeral date, at which point his coffin will be transferred to St Peter's Basilica.
In the meantime, the day-to-day running of the tiny Vatican City state will be handled by the Camerlengo, a senior cardinal, currently Dublin-born Cardinal Farrell.
World leaders praised the pope for having strongly defended social justice and the rights of migrants.
Britain's King Charles, who met Francis during a state visit earlier this month, said the pope had "served with such devotion".
French President Emmanuel Macron said the pope had always been "on the side of the most vulnerable and the most fragile" and that he had stood for "brotherly humankind".
Italy's Prime Minister Giorgia Meloni said "a great man has left us" in a statement, while Argentina's President Javier Milei pointed to his compatriot's "goodness and wisdom" despite their "differences".
European Commission President Ursula von der Leyen said Francis had "inspired millions... with his humility and love so pure for the less fortunate".
US Vice President JD Vance, a Catholic convert who briefly met Francis on Sunday while on a trip to Rome with his family, said his "heart goes out" to Christians. The White House wrote "Rest in Peace" on X.
Ukrainian President Volodymyr Zelenskiy said he was grieving and Russian President Vladimir Putin praised the pope's promotion of dialogue between the Orthodox and Catholic churches.
Italy's Serie A football league called off all the day's matches and the country's Olympic committee called for all sporting events due to take place there on Monday to be postponed.
Spain announced three days of mourning while the bells at the Notre Dame cathedral in Paris rang out 88 times and the city said the lights would be turned off at the Eiffel Tower on Monday evening.
Francis's pontificate was also marked by pushing through governance reforms and tackling the scourge of clerical sex abuse of children.
But critics accused him of creating doctrinal confusion and failing to defend traditional Catholic beliefs on key issues such as abortion and divorce.
Francis's desire to chart a different path was evident right to the end, with his decision to be buried not in St Peter's Basilica but in Rome's Santa Maria Maggiore basilica.
He will become the first pope in more than 100 years to be laid to rest outside the Vatican.