Mother Teresa of Calcutta, known as the "saint of the gutters" during her life
, was declared a saint of the Roman Catholic Church by Pope Francis on Sunday, fast-tracked to canonization just 19 years after her death, Reuters reports.
Around 120,000 people packed St. Peter's Square at the Vatican for a service to honour the tiny nun, who worked among the world's neediest in the slums of the Indian city now called Kolkata and become one of the most recognisable faces of the 20th century.
A Nobel peace laureate, her legacy complements Pope Francis's vision of a humble church that strives to serve the poor and the festivities in her honour are a highlight of his Holy Year of Mercy, which runs until Nov. 8.
Standing under a canvas hung from St. Peter's Basilica showing the late nun in her blue-hemmed white robes, Francis said she was a "dispenser of divine mercy" and held world powers to account "for the crimes of poverty they created".
"For Mother Teresa, mercy was the salt which gave flavour to her work, it was the light which shone in the darkness of the many who no longer had tears to shed for their poverty and suffering."
Francis also said it might be difficult to call the woman "Saint" as people felt so close to her they spontaneously used "Mother".
The Church defines as saints those believed to have led such holy lives they are now in Heaven and can intercede with God to perform miracles - two of which are needed to confer sainthood.
Mother Teresa is credited with healing an Indian woman from stomach cancer in 1998 and a Brazilian man from a brain infection in 2008
. The Brazilian, Marcilio Andrino, and his wife attended the ceremony and were blessed by the pope.