Rio de Janeiro (CNN) The Olympic Games are 31 days away -- and Rio de Janeiro is in crisis.

Violence is on the rise, and police officers are at loggerheads with the Rio state government after claiming they've not been paid for months.

The message from police to tourists is clear: We won't be able to protect you.

The state's police officers vented their anger Monday with a sign saying, "Welcome to Hell," outside Rio's main airport. "Police and firefighters don't get paid, whoever comes to Rio de Janeiro will not be safe," the sign said.

And it's not just those coming from abroad who may be in danger -- locals are losing patience, too.

That's the harsh reality in the favelas around Rio, according to one resident, as the city gears up to host the 2016 Olympics amid increasing concerns over police brutality and the officers' ability, and desire, to keep people safe.

"It seems like there is an order (from authorities) to put fear in people so they stay calm, so they don't cause trouble in the city because the foreigners can't see that the city is chaotic," Higor da Silva, a resident of the Mare favela, told CNN.

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"They (state police) don't care if there is a child in the middle -- they shoot their target."

State security officials told CNN they have taken measures over the years to expel officers who use excessive force and say they have decreased the use of heavy weapons.

Rio de Janeiro Mayor Eduardo Paes told CNN this week the state was doing a "terrible" job in regard to security in the lead-up to the games, set to kick off August 5.

"It's completely failing at its work of policing and taking care of people," Paes said.

But on Tuesday, Brazilian officials put on a united front to assure the world that Rio was up to the task of hosting sport's greatest showpiece.

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"We are ready to start the games," Carlos Arthur Nuzman, president of the Rio 2016 Organizing Committee, said at a press conference in the city, adding that the event "could start today."

"They will be a maximum success in this beautiful city of ours," he said.

Speaking alongside him, Paes reiterated the announcement but cautioned that visitors should not expect to find a city that operates like Chicago, New York or London.

"Our development stage is different," he said.

The government later tweeted that every venue for the quadrennial event is ready, and the primary press center was open. It said there will be 85,000 security personnel at Olympic sites and important places like the city's airports.

Every #Rio2016 venue is now ready, and the Main Press Centre at the Barra Olympic Park opens today. — Brazil Gov News (@BrazilGovNews) July 5, 2016

Bailout

Rio de Janeiro state, which controls the region's military police force, issued an executive order requesting emergency funds from the federal government to pay officers their bonuses and overtime.

The 2.9 billion-real bailout (roughly $850 million) was made available last week after acting Gov. Francisco Dornelles said the games could be a "big failure" without the funds. It's believed that the back pay will be distributed this week.

"We are numbers, nothing more," one officer, who wished to remain anonymous, told CNN.

Police and firefighters protest over pay Monday at the Rio de Janeiro airport.

"You encounter a drug trafficker armed with lots of ammunition and you only have only 20 bullets. It is absurd."

Two officers, interviewed by CNN on condition of anonymity, said the city's scant resources are used to patrol tourist hotspots such as Copacabana instead of favelas where criminal gangs run the streets.

They have risked speaking out because they say they've watched fellow officers die to preserve Rio's image -- not to protect its people.

"We have a very common saying here in Brazil -- for the English to see," one of the officers said. "I believe that the politicians here are doing everything for the English to see."

Death rate rising

According to figures from Brazil's Public Security Institute published last week and distributed by Amnesty International, on-duty officers killed 40 people in May alone -- police killed 17 people during the same period last year.

Last year, police killed at least 307 people in Rio -- a figure that accounts for one in every five homicides there, according to Amnesty.

According to the figures, police killed 645 people in the state in 2015, and many of the victims were young, black men from favelas and poor communities.

"Brazil has one of the highest levels of homicides in the world, with around 42,000 people killed with guns every year," Atila Roque, Amnesty International's Brazil executive director, said in a statement.

"Those living in the most marginalized areas of the city are disproportionally affected by this crisis."

When Brazil hosted the World Cup in 2014, police in Rio de Janeiro state killed 580 people, a 40% increase from the previous year, the rights group said.

Problems mounting

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