If security was judged by looks then Rio is locked down, by sea and on land.

Tourist police cruise the streets along iconic beaches, a reassuring presence.

“It’s enormous. For us in Brazil this is the largest security operation in our history,” said Rio’s Under Secretary of Public Safety Edval Novaes.

“We have in total 80,000 men, that’s including the police, the emergency services and the Brazilian armed forces.

“All threats are being considered, be they local or foreign threats such as terrorism.

“This is being researched by intelligence and by operational police forces in order to avoid and confront any possible threat.”

Yet Rio’s crime rate is well-known and Olympic visitors are cautious.

Police have been drafted in to screen at competition venues after a private security company was sacked.

But how motivated are they?

After salaries were crunched, they had a less than welcoming note for Olympic arrivals.

The Olympics are happening in the midst of a law-and-order crisis for Rio residents.

The number of murders spiked in the first half of this year, while human rights advocates say poorly trained forces respond with disturbing brutality made worse by the Olympics.

Amnesty International human rights advisor Renata Neder says the number of people killed by police in three months this year was double that of the same period last year.

Ms Neder says this has corresponded with the hosting of major sporting events.

“We hosted the Pan American Games in 2007 and that year the number of people killed by the police in Rio increased around 30 per cent in comparison with the previous year,” she said.

Vitor Santiago was shot and paralysed during a World Cup security crackdown.

“The security forces in Rio are incompetent,” he said.

“There’s no training. You see a lot of police who are incapable of taking care of people.”

The Olympics has also brought prospects of a fresh danger to Brazil’s shores in terrorism.

Sociologist Glaucio Soares says there are fears security forces will not be able to cope with any potential terrorist threat.

“We’ve never been target of terrorist activity,” he said.

“It is a major weakness because … we don’t have the experience.”

Chad Carter rents out properties and security to rich clientele coming to Rio and says the city’s been portrayed unfairly.

“Luxury rentals down by eighth because of scare,” he said.

Mr Carter says Olympic visitors just need to use common sense.

Rio will need a lot more than that when the Games circus leaves town.