Rio 2016 chief executive Sidney Levy has admitted that security fears are his biggest worry ahead of the Games.

"Differently from Zika, security's at the top of my list - the very top of my list," Levy said.

"We should never forget that these days we live in a society that's very in danger."

Widespread protests took place at the Rio Galeão-Tom Jobim International Airport in which demonstrators held a large sign in which the English message “Welcome to hell: police and firefighters don’t get paid. Whoever comes to Rio de Janeiro will not be safe," was written.

Other protesting officers held up placards predicting how “there won’t be any Games without a salary,” and that “Rio will grind to a halt.”

"The police's priority is the people, the Government's priority is the Olympics," read one banner at a separate protest on the steps of the Rio de Janeiro State Assembly, considered a "warning" to the authorities. 

Those demonstrating claim their wages are too low to live on, while they are allegedly owed overtime salaries.

They also claim they are receiving unsatisfactory support for the increasingly dangerous work they are undertaken in communities ravaged by drugs gangs and gun crime.

"At the stations we don't have paper or ink for the printers, there's no one to come in to clean and some stations don't have a water supply anymore so the toilets are not functioning," one officer in an elite unit considered key to providing security for the Olympics told Agence France-Presse.

"Members of the public bring toilet paper to us."

The financial crisis in the State Government coincides with escalating levels of crime.

“Our patience has run out,” said Fabio Neira, head of a police union,

“We are living on subsistence levels now.

"We don’t want to do anything radical but the Government has forced us to this point...a total shutdown cannot be ruled out.”

Rio interim State Governor Francisco Dornelles has admitted this week how the Games could be a "big failure" if appropriate arrangements are not made regarding security and transport plans.

He declared an unprecedented “state of public calamity in financial administration” earlier this month, which could threaten “the fulfilment of the obligations as a result of the Olympic and Paralympic Games Rio 2016”.

Interim President, Michel Temer, has already agreed to disburse federal funds to cover Rio’s shortfall, prioritising any projects considered necessary for the Games.

But Dornelles said they are still awaiting a BRL$2.9 billion (£579 million/$860 million/€720 million) payout from the Federal Government.

Security is a major concern at Rio 2016 after a series of muggings affecting athletes training for the Games.

Australia's six-time Paralympian Liesl Tesch was robbed at gunpoint close to the Guanabara Bay sailing venue last week, while members of both the Spanish and British sailing teams have also been targeted.

A total of 85,000 security forces are expected to be deployed during the Games.

Concerns remain, however, over their accommodation and to what extent the financial crisis affecting the State Government will hinder their activities.

In a fact sheet on security produced in April and since sent to insidethegames, the nine biggest security concerns surrounding the Games were described as "Terrorist or sabotage actions of any kind", "Violent actions committed during protests", "Urban crime and violence," "Risks to the urban mobility system," "Risks to public health", "Risks to essential services," "Cyber-attacks," "Natural phenomena," "Incidents and disasters".

Military state police involved in the protests are expected to be primarily responsible for security at Games venues, official routes, public roads and live sites, as well as protecting dignitaries, the Olympic Family, workforce and spectators.

Civil police also involved are expected too be more responsible for emergency response work, including in response to terrorism threats.