Pope Francis held his first open-air mass in Africa on Thursday with huge crowds hailing heavy rains as “God’s blessing” as they sung and danced in the Kenyan capital.

Thousands of people queued through the night braving torrential downpours to take part in the mass.

The 78-year-old pontiff received a tumultuous welcome as he arrived in an open-topped Popemobile, smiling and waving as worshippers cheered, ululated and raised their hands in the air.

The mass at the University of Nairobi – also shown on giant television screens in neighbouring parks – was the pope’s first major public appearance and a highly-anticipated part of his three-day visit to Kenya.

Kenyan media said at least 200,000 people – including 9,000 priests and 60 cardinals, archbishops and bishops – crammed into the park, smiling despite the rain.

“It is beautiful,” said Sister Rachel, a nun. “We all sat through the rain and were not worried.”

“These are special days,” said worshipper Mathew Kyalo Muluu. “I’m happy everybody came. We came in full force.”

In some places, so many people tried to enter the grounds that security forces were overwhelmed and could be seen using sticks to beat people back as they surged through the gates, an AFP correspondent said.

Thousands of police and troops have been deployed across the city as the pontiff makes his first visit to Kenya on a six-day trip which will also take him to Uganda and Central African Republic (CAR).

During the mass punctuated by frequent bouts of lively singing and dancing, Francis made a special appeal to young people to work “to shape a society which is ever more just, inclusive and respectful” of human dignity.

“May you always be concerned for the needs of the poor, and reject everything that leads to prejudice and discrimination,” he told the crowd, which included President Uhuru Kenyatta.

Over his traditional white robes, the pope wore a garment embroidered with Maasai-style beading specially made for him by a group of tailors living in Kangemi slum which he will visit on Friday.

Francis has warned the world is facing a “grave environmental crisis” just days before the start of a key UN climate summit in Paris, and he was expected to give a key speech on climate issues later on Thursday while visiting the headquarters of the United Nations Environment Programme (UNEP).

Worshipper Samuel Masibo Wataka said the visit was a “great blessing for our country, for the Christian fraternity, and everyone in Africa.”

As the rain fell, a sea of brightly-coloured umbrellas popped up, stretching as far as the eye could see, some in the white and gold of the Vatican flag.

On the first full day of his visit, Kenya’s newspapers homed in on his choice of vehicle to travel from the airport: a simple grey saloon car.

“Modesty at its best as pope rides in simple car,” The Standard newspaper said, noting the stark contrast with the government’s large luxury “fuel guzzlers”.

Ahead of the mass, Francis met with leaders of different faiths, speaking out against the radicalisation of young people and “barbarous attacks” carried out in the name of religion.

“All too often, young people are being radicalised in the name of religion to sow discord and fear, and to tear at the very fabric of our societies,” the pope said nearly two weeks after young jihadists, many of them French, killed 130 people in a gun and suicide attacks in Paris.

“The God whom we serve is a God of peace. His name must never be used to justify hatred and violence.”

Kenya has suffered numerous attacks since sending its army into neighbouring Somalia in 2011 after a string of kidnappings it blamed on Al-Qaeda's East Africa branch, the Shebab.

The Islamist rebels have staged a string of attacks in Kenya, including an April massacre at Garissa university in which 148 people died and a 2013 assault on Nairobi's Westgate shopping mall that killed 67.

The leader of the world’s 1.2 billion Catholics has also urged Kenya’s leaders to work with “integrity and transparency” and to battle inequality in comments alluding to the corruption and inequality that blights the country. (AFP)

•Photo courtesy Photo/Carl de Souza shows crowds who braved torrential rains to queue for the mass by Pope Francis . . . today in Nairobi.

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