VATICAN CITY (REUTERS) - Pope Francis' Holy Week and Easter services, which normally draw tens of thousands of people, will be held without the public attending because of the coronavirus outbreak, a step believed to be unprecedented in modern times.

It was not clear how the massive events will be scaled down but sources said officials were studying ways to hold them in indoor locations, including St. Peter's Basilica and the Sistine Chapel, with small representative groups attending.

A note on the website of the Vatican department that organises papal events also said that until Easter Sunday on April 12, his general audiences and Sunday blessings would continue to be seen over the Internet and television without public participation.

The exclusion of the public from the pope's general audiences and Sunday blessings previously had been expected to continue only until March 18.

The Holy Week services, which begin on Palm Sunday, lead up to Easter, the most important day of the Roman Catholic liturgical calendar for the world's 1.3 billion members.

Palm Sunday, which commemorates Jesus' entry to Jerusalem, usually takes place in St. Peter's Square, which traditionally is decorated with olive trees while those in the crowd hold up palm branches.

Another main Holy Week event, the Way of the Cross procession on Good Friday, takes place around Rome's ancient Colosseum.

The main event is the Easter Sunday Mass and the pope's twice yearly "Urbi et Orbi" blessing and message from the central balcony of St. Peter's Square.

The Netherlands usually fly in tens of thousands of flowers to decorate the papal altar and the entire square but the Dutch ambassador to the Vatican, Caroline Weijers, said last week that there would be no flowers this year.

Italy, which has been in a national lockdown for a week, has been hit harder that any other European nation. The country's death toll rose to 1,441 on Saturday and the total number of cases rose to 21,157 from 17,660.

The pope, the Vatican - a tiny city-state surrounded by Rome - and the church in predominantly Catholic Italy have all been forced to modify centuries of tradition because of the coronavirus outbreak.

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Catholic bishops around the world were deciding how to deal with the pandemic in their own dioceses and what guidance they should give to the faithful.

In Italy, as elsewhere, masses have been cancelled to avoid people gathering. Bishops have told the faithful they are not obliged to attend mass on Sundays and Holy Days. Bishops have urged the faithful to participate via television and the Internet.