Civil Police via AFP / Getty Images

Mugshots released by Brazil's Civil Police showing Jonathan Froudakis de Souza, 20, left, and Wallace Aparecido Silva, 22, who allegedly raped an American tourist in a minibus in Rio de Janeiro on Saturday.

An American woman was gang raped and beaten aboard a public transport van while her French boyfriend was shackled, hit with a crowbar and forced to watch the attacks after the pair boarded the vehicle in Rio de Janeiro's showcase Copacabana beach neighborhood, police said.

A third man, aged 21, was arrested for the attacks, which took place over six hours starting shortly after midnight on Saturday, police said in a Tuesday statement. Two men aged 20 and 22 had already been taken into custody for the attacks, police said, and a young Brazilian woman has come forward to say that she, too, was raped by the same men in the van on March 23.

"The victims described everything in great detail, mostly the sexual violence," police officer Rodrigo Brant told the Globo TV network. "Just how they described the facts was shocking — the violence and brutality. It surprised even us, who work in security and are used to hearing such things. Their report shocked us."

The incidents raise new questions about security in Rio, which has cracked down on once-endemic drug violence in preparation for hosting next year's football World Cup and the 2016 Summer Olympic games. The city will also be playing host to World Youth Day, a Roman Catholic pilgrimage that will be attended by Pope Francis and is expected to draw some 2 million people in late July.

Officials from the local Olympic and World Cup organizing committees didn't immediately respond to requests for comment.

The attack also drew comparisons with the fatal December beating and gang rape of a young woman on a New Delhi bus. Six men beset a 23-year-old university student and male friend after they boarded a private bus, touching off a wave of protests across India demanding stronger protection for women. Officials there say tourism has dropped in the country following the attacks.

In the Brazil case, a police statement said the suspects forced other passengers to get out of the van and then raped the female tourist inside the vehicle, which was one of a fleet of vans that serve bus routes and seat about a dozen people.

Such van services are often linked to organized crime in Rio, particularly the militias largely composed of former police and firemen that control large swaths of the city's slums and run clandestine services such as transportation and sell cooking fuel and illegal cable TV hookups. In general, tourists avoid the vans and opt for regular buses or taxis.

Sexual assaults on tourists are not common in Rio, with muggings and petty crime reported more frequently.

During the assault, the two foreigners were driven to the poor neighborhood of Sao Goncalo, where the two suspects were apprehended, a police statement said.

Reports said the two foreigners had been studying Portuguese in Rio for about a month and both left Brazil following the attack.

The police statement said that one victim's cellphone was found in the suspects' possession. The suspects had also used a debit card belonging to one of the victims at two gas stations, it said.

The Globo television network broadcast surveillance camera images of two men filling up the white van and showed police images of a crowbar the suspects used to beat and intimidate the victims. The victims positively identified the two suspects.

In an interview with Globo television, commanding officer Alexandre Braga, who heads the Rio police unit specializing in crimes against tourists, said the suspects had gone on a sex crime spree.

"The characteristics of both crimes, both the Brazilian case and the one with the foreigners, lead us to believe that they [the suspects] wanted to have a 'party of evil,' in quotes," Braga said. "The principal motive appears to have been the satisfaction of their lust."

He added that the robbery and other crimes appear to have been "secondary."

Multiple calls to police seeking further details on Tuesday were not immediately returned.

In Brazil, more than 5,300 cases of sexual assault were reported between January and June 2012, according to the country's Health Ministry.

Related:

Female tourists shun India after gang-rape, murder

Six arrested in India for gang-rape of Swiss tourist

This story was originally published on Mon Apr 1, 2013 5:26 PM EDT

Bike stations throughout Rio de Janeiro allow people to rent bikes online or via text message.

Rio de Janeiro has long been a tropical flower with thorns. Set in one the world’s most stunning natural locations, the pulsing metropolis has suffered from persistent crime and weak infrastructure. Most recently, three downtown buildings collapsed on Jan. 25, leaving at least 17 people dead.

This tragic setback aside, security and infrastructure are generally improving and travelers are taking notice.

Riotur, the city’s tourism office, says the city expects to get 3 million more visitors this summer (January through March) than over the same period last year. The Brazilian Association of Hotels in Rio is predicting 90 percent hotel occupancy through the end of the season, the best in years.

A combination of events has boosted Rio's standing. A booming economy has vaulted millions of people into the middle class. Huge discoveries of offshore oil has encouraged optimism that economic advances will not evaporate like false starts of the past. And the impending global spotlight of the 2014 FIFA World Cup and the 2016 Olympics have forced the city to finally make much needed investments in public safety and infrastructure.

Known as “The Marvelous City,” Rio is starting to live up to its potential.

One year has passed since the police crackdown on drug traffickers that controlled many of the city’s favelas, those impoverished hillside communities that house millions. The city has made a concerted effort to root out organized crime from the communities, bringing peace and incorporating them into wider society. The police has embedded small teams in the neighborhoods that are tasked with crime prevention and delivering social services never before offered in those areas.

Crime has plummeted. São Paulo-based American ex-pat, Marjan Harbison, who recently took her family to Rio for the first time, said, "I was impressed by how safe I felt, even compared to São Paulo," the largest city in Brazil.

There are so many fewer car thefts in Rio this year that the once crushing cost of car insurance has fallen in kind. And in this upbeat environment, infrastructural improvements are arriving, slowly but surely.

“City hall is working hard on the infrastructure," says Rubem Machado, a spokesperson for Rio’s Commission of Sport and Recreation. "We’re getting new roads and the revitalization of the Port [the future site of the Olympic Village] is already under way. The main stage for the World Cup will be Maracanã soccer stadium and its remodel is in progress too.”

However, even Machado admits “the modernization of the (two) airports is still really behind schedule.”

But other changes in the shorter terms are already making the city friendlier for visitors. New subway (Metró) stations at Ipanema beach and an upcoming new line to Barra da Tijuca beach are improving ease of transport and accessibility. Paris-style bike stations are popping up throughout the city that allow people to rent bikes online or via text message. And the most famous beaches, Ipanema and Copacabana, are getting new public bathrooms and workout stations.

Harbison, the American ex-pat, was pleasantly surprised by the cleanliness and order of the city. “Rio may have had a reputation in the past, but it’s clear that things are improving,” she said.

Slideshow:

Antonio Scorza / AFP/Getty Images

The 2016 Summer Olympics will be held in Rio de Janeiro, marking the first time a South American destination will host the Games. Take a visual tour of the Brazilian city's beautiful beaches, landscapes and people.

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