Tens of thousands of people lined the streets of Manila, cheering as Pope Francis began his first visit to Asia's largest Catholic nation amid one of the biggest security operations in Philippine history.

The other pontiffs to visit the Philippines were both targets of assassination attempts, prompting the deployment of nearly 50,000 soldiers and police in the capital and in the central Philippine province of Leyte for his weekend trip there.

Pope Francis Philippines
Pope Francis tries to hold on to his cap after it was blown off by the wind as he was disembarking at a military airbase in ManilaTed Aljibe/AFP
Pope Francis Philippines
Pope Francis embraces Philippine Cardinal Luis Antonio Tagle upon his arrival at Villamor Air Base in ManilaStefano Rellandini/Reuters
Pope Francis Philippines
Pope Francis and President Benigno Aquino listen to national anthems at the Villamor Air Base in ManilaOsservatore Romano/Reuters

Earlier this week, the Vatican denied Italian newspaper reports that US and Israeli intelligence officials had informed the Vatican that there could be an imminent attack by Islamist militants.

Interior Secretary Manuel Roxas said President Benigno Aquino was willing to serve as Francis' "personal bodyguard" to ensure his safety. In a televised address on Monday (12 January), Aquino appealed to Filipinos to follow security rules after two people were killed in a stampede during a religious procession on Friday.

In 1970, a Bolivian artist dressed as a priest tried to stab Pope Paul VI when he arrived at Manila airport. The Pope sustained minor chest wounds from the attack.

In 1995, a group of Islamist militants, including the mastermind of the 1993 World Trade Center bombing, conspired to assassinate Pope John Paul II in Manila. But an accidental fire in an apartment in Manila led to the discovery of the bomb plot days before the Pope's visit.

Asked by reporters aboard the papal plane to Manila if he felt vulnerable to an assassination attempt or an attack, Francis said he was more worried about others rather than himself, and that he was confident about security measures in the Vatican and during his trips.

"I am in God's hands," he said, joking about having asked God to spare him a painful death. "If anything should happen to me, I have told the Lord, I ask you only to give me the grace that it doesn't hurt because I am not courageous when confronted with pain. I am very timid."

Church bells tolled across the Philippines when the papal plane touched down in Manila, and crowds inside the airport and those lining the streets into the capital jumped, clapped and cheered when Francis stepped out of the plane.

Pope Francis Philippines
Pope Francis waves to the faithful from the Popemobile upon his arrival in ManilaLam Yik Fei/Getty Images
Pope Francis Philippines
Huge crowds gather in Manila, hoping to catch a glimpse of the PopeNoel Celis/AFP
Pope Francis Philippines
People wait for the arrival of Pope Francis in ManilaJohannes Eisele/AFP
Pope Francis Philippines
A well-wisher holds a cross as she waits for the Pope's arrival in ManilaJohannes Eisele/AFP
Pope Francis Philippines
Sick people and their families wait for the motorcade of Pope Francis to pass along a main street in ManilaPaul Barker/Reuters
pope manila
A boy receives medical attention after collapsing while waiting for the arrival of Pope Francis in ManilaLisa Maree Williams/Getty Images

The 78-year-old pontiff will bring a message of compassion to millions of poor Filipinos suffering from the effects of corruption and decades-old insurgencies.

He will visit the central province of Leyte, which is still struggling to recover from Typhoon Haiyan that killed 6,300 people in 2013. About two million people are expected to attend an open-air mass on Saturday at Tacloban City airport, almost completely destroyed by Haiyan.