Pope Leo XIV expressed thanks for the 'affection, support and prayers' of his former parishonersImage: AFP

Pope Leo XIV was greeted by another enormous crowd on Friday as he arrived at Pampas de Pimentel, a vast desert park outside the northern Peruvian city of Chiclayo, to celebrate an outdoor Mass in a diocese that he served as bishop for eight years before being summoned to Rome in 2023, where he was later elected pontiff.

The Vatican estimates that roughly 1.5 million faithful braved scorching sun and heat of 31 degrees Celsius (87 degrees Fahrenheit) to attend.

The event was the centerpiece of Leo's 12-day South American tour, throughout which an estimated 12 million people have turned out at stops in Uruguay and Argentina and now Peru.

Some 1.5 million people braved sun and heat to be with Pope Leo in ChiclayoImage: Pilar Olivares/REUTERS

'Padre Roberto' returns home as 'Papa Leon'

Pope Leo, born Robert Prevost in Chicago, Illinois, had already referred to Peru, where he served as a missionary for some 20 years, as his homeland in remarks delivered on Wednesday.

Beyond US and Vatican citizenship, Leo also holds a Peruvian passport.

Leo, whom locals still refer to as "Padre Roberto" and "amigo," arrived from the capital Lima on Friday morning in a plane adorned with stickers reading "Leo XIV flies home." The leader of the Catholic Church's 1.4 billion members will remain in Chiclayo until Sunday.

An agricultural and commercial hub on the Pacific coast, Chiclayo is Peru's fourth largest city and has a population of 700,000. Beyond locals, many of those attending Mass on Friday told reporters that they had journeyed from far-flung regions and even neighboring countries to receive the pope's blessing.

The crowds that Leo has attracted throughout his trip, undertaken shortly after he underwent surgery for lung cancer in Rome, have grown along the way, with the largest gathering coming in Lima on Wednesday, where an estimated 3.5 million people turned out.

Pope Leo XIV celebrated Friday's Mass in a temporary structure in the coastal desert at Pampas de PimentelImage: Andrew Medichini/AP Photo/dpa/picture alliance

Pope overwhelmed with emotion, thanks Chiclayo faithful for their prayers

Though normally reserved, Leo has openly displayed his emotions since returning to Peru — laughing, singing and tearing up while interacting with crowds of faithful both young and old.

After making his way through the massive crowd to celebrate Mass on Friday, Leo began his sermon with words of thanks.

"What a joy it is to return to Chiclayo!" Leo said at the start of his homily, "It is a blessing for me to be with you once again."

"As I look your faces, a prayer of thanksgiving to the Lord arises in my heart for the blessing you have been and continue to be in my life."

"Thank you for your affection, support and prayers, especially for my health during this time of trial which, with God's help, I am overcoming," Leo told the crowd.

Pope Leo starts jam-packed South America tour just weeks after surgery

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Pope Leo will deliver remarks at university named for role-model missionary

On Friday afternoon, the pontiff will deliver a speech at Chiclayo's St. Turibius de Mogrovejo Catholic University, where he once served as chancellor.

The institution is named after a sixteenth century Spanish missionary who would become the first archbishop of Lima. He served as a role model for Leo during his own ministry.

Mogrovejo was known to travel long distances on horseback to spread the gospel, as well as for standing up for the rights of indigenous and enslaved peoples.

Leo, too, is remembered for his outreach and for championing human rights and social justice, especially for the poor.

Before becoming Pope Leo XIV, Bishop Robert Prevost spent nearly two decades caring for the poor and underprivileged in northern PeruImage: Elkin Cabarcas Mora/Janinna Sesa's personal archive/picture alliance