Tens of thousands of people have welcomed Pope Francis in the Brazilian city of Rio de Janeiro in his first overseas visit as head of the Catholic Church.
The Pope is in Brazil for a week-long visit and will attend the Roman Catholic World Youth Day festival.
On Monday, he joined a parade through the streets of Rio in an open vehicle and in a speech soon after his arrival urged young Catholics to "make disciples of all nations", the BBC reports.
"I came to meet young people coming from all over the world, drawn to the open arms of Christ the Redeemer," he said at the governor's palace, referring to Rio's famous vast statue of Jesus. "They want to find a refuge in his embrace, right near his heart to hear his call clearly and powerfully."
The Pope then attended an official event at the state governor's palace with President Dilma Rousseff.
After he left, hundreds of demonstrators clashed with police and threw petrol bombs in the latest protests against corruption. Some were also reportedly unhappy about $US53 million in public funds being spent for the pontiff's visit.
Some 30,000 security staff - army and police are on duty throughout his visit.
In a separate development, the military said a home-made explosive device had been discovered at a shrine between Rio and Sao Paulo that the Pope is due to visit on Wednesday.
The device at the Shrine of Our Lady of the Conception of Aparecida was described as being "of low power" and was destroyed.
More than 1 million young people are expected to gather for the Roman Catholic World Youth Day festival, which takes place every two years.
The Argentina-born Pope - who became head of the Catholic Church in March this year - is due to lead a prayer service at Copacabana beach on Thursday.