Hundreds of thousands gathered in St. Peter's Square on Sunday (April 27), a day after Pope Francis' funeral, for another ceremony to honor him on the second of nine official days of mourning for the global Catholic Church.

But instead of world leaders like U.S. President Donald Trump, who attended the funeral, the vast square and surrounding streets were filled with what Italian police estimated were 200,000 mainly young people, many wearing scouting uniforms or colorful T-shirts.

Sent as delegations from across Italy and several other countries, they had planned to come to Rome for a now-postponed ceremony to proclaim the first Catholic saint from the millennial generation.

Instead of honoring Carlo Acutis, an Italian boy who died from leukemia aged 15 in 2006, they were now honoring Francis, who died at the age of 88 on April 21 after 12 years leading the 1.4-billion-member Church.

Ahead of Sunday's service, the young crowds pressed down the main boulevard through Rome towards the Vatican. Shouts of "viva Francesco" (long live Francis) and "il gioventu del papa" (the pope's youth) were heard.

Cardinal Pietro Parolin, the Vatican's secretary of state, led the ceremony. In his sermon, he told the young people present that they should hold onto their feelings of sorrow for Francis' death to 'welcome his legacy and make it part of our lives'.

(Production: Chiara Rodriquez)