San Francisco Frontiers - Nuns, ex-Satanic priest among seven new saints created by Pope Leo

Also canonised during the solemn ceremony under sunny skies in the vast plaza on World Mission Day were three nuns who dedicated their lives to the poor and sick, and former Satanic priest Bartolo Longo.

The Italian lawyer born in 1841 subsequently rejoined the Catholic faith and went on to found the Pontifical Shrine of the Blessed Virgin of the Rosary of Pompeii.

Huge portraits of the seven were unfurled from windows over the square as Leo, the first US pope, exited St Peter's Basilica dressed in a ceremonial white cassock with a white mitre on his head, preceded by white-clad bishops and cardinals.

Cardinal Marcello Semeraro, prefect of the Diacastery for the Causes of Saints, read aloud profiles of the seven to applause from the crowd, before the canonisation formula read by the pope, a decree in which they are officially declared saints.

The rite of canonisation was the second for the former Robert Prevost since he was made leader of the Catholic Church on May 8.

Last month, he proclaimed as saints Italians Carlo Acutis -- a teenager dubbed "God's Influencer" who spread the faith online before his death at age 15 in 2006 -- and Pier Giorgio Frassati, considered a model of charity who died in 1925, aged 24.

Canonisation is the final step towards sainthood in the Catholic Church, following beatification.

Three conditions are required -- most crucially that the individual has performed at least two miracles. He or she must be deceased for at least five years and have led an exemplary Christian life.

- Martyrs, humanitarians -

Those made saints Sunday were Peter To Rot, a lay catechist from Papua New Guinea killed during the Japanese occupation during World War II, Armenian bishop Ignazio Choukrallah Maloyan killed by Turkish forces in 1915, and Venezuela's Jose Gregorio Hernandez Cisneros, a layman who died in 1919, whom the late Pope Francis called a "doctor close to the weakest".

Also from Venezuela was Maria Carmen Elena Rendiles Martinez, a nun born without a left arm who overcame her disability to found the Congregation of the Servants of Jesus before her death in 1977. She becomes the South American country's first female saint.

The Italian nuns canonised are Vincenza Maria Poloni, the 19th-century founder of Verona's Institute of the Sisters of Mercy, which cares primarily for the sick in hospitals, and Maria Troncatti of the Daughters of Mary Help of Christians.

In the 1920s, Troncatti arrived in Ecuador to devote her life to helping its indigenous population.

V.Mitchell--SFF