RIO DE JANEIRO - Since taking the helm of the world's biggest church in March, Pope Francis has waded into massive crowds with minimal protection to hug children and wash the feet of the faithful.
He has surrounded himself with everyday worshippers at every turn, winning acclaim that he's breaking down barriers between the Vatican and the world's 1.2 billion Catholics.
Yet for Brazilian security officials charged with protecting the 76-year-old pontiff with the common touch, his seven-day visit this week is an uncommon security challenge.
In his first international trip as pope, Francis has built much of his schedule in the world's biggest Catholic country around high-profile events that send him straight into unpredictable, potentially chaotic environments - without the protection of the bulletproof popemobile used by his two predecessors.
On Thursday, the pope will visit a tiny chapel founded in 1971 in the Varginha slum, one of Rio's more than 1,000 hillside shantytowns. Many such slums cower under the control of dangerous drug gangs or deadly militias made up mostly of former and current police and firefighters.
Police invaded Varginha in January to clear out traffickers, but the gangs remain a shadowy presence there.
The next day, Francis will hit Copacabana beach to walk the Stations of the Cross among an expected 1 million young Catholics gathered for World Youth Day festivities. Vatican officials have said he'll travel to the beach past thousands of devotees in an open-topped vehicle, a plan that would put the thousands of police and soldiers dispatched to protect the pope on high alert and require more plainclothes security.
Brazil's justice and defense ministers, along with a top army commander, urged the pope to use an armored popemobile instead, but the Vatican has responded that Francis likes to jump in and out of his vehicle to greet the faithful, which wouldn't be possible in the more protected vehicle.
"The bulletproofing would lessen our worries. It'd be better if he had it," said Gen. Jose Abreu, the top officer overseeing the military's role in the security scheme. "It's a personal choice, and we'll respect it, but it's not remotely pleasant for security forces."
On the top of everyone's minds are the massive and sometimes violent anti-government protests that swept this continent-sized country last month. They've continued, albeit with fewer people, less than a week before Francis' arrival today.
Last week, a small protest in Leblon, one of Rio's poshest neighborhoods, erupted into looting and destruction, with demonstrators smashing storefronts, defacing street signs and setting piles of garbage on fire.
A handful of protests are planned. If violence breaks out near the pope, the world may once again see images of demonstrators enveloped by clouds of tear gas, stun grenades ricocheting off stately buildings and rubber bullets whizzing through the air.
Jose Beltrame, the top security official for Rio de Janeiro state overseeing the police who will counter any violent protests, said he's certain his officers "are ready to host the pope" because they know his set agenda and have a plan in place.
However, Beltrame acknowledged that the protests are an unknown factor and that each demonstration would need to be approached differently depending upon how it unfolds.
"The challenges of the protests are different. The police have to be flexible and adapt, because there is no coordinated agenda (of protests)," he said. "We're vigilant, but it depends upon how they happen, when they happen, which is information that we don't fully have."
Joe Biundini, a Brazilian-born former U.S. Marine who heads the FAM International Group security firm, warned that much will depend on police response to any protests.
"If you see the police doing something stupid, like violently attacking protesters, that could cause some very serious problems," Biundini said.
Security officials have said the stiffest security challenge will be providing security for the pope's two mass events on 2 1/2-mile-long Copacabana beach.