Rio in a race for readiness as Olympics countdown begins

A crime-plagued, cash-strapped Rio de Janeiro today enters the one-month countdown to becoming the first South American city to host the Olympics.

Stadiums are all ready -- barring finishing touches -- and within weeks, Brazil expects to greet at least 5,00,000 tourists for the August 5-21 Games.

The mayor, Eduardo Paes, and Brazil's Olympic committee boss Carlos Nuzman were to give a news conference marking the milestone in Rio's epic effort to transform from a beautiful but crumbling city to glittering stage for the world's most-watched event.

"The city is 100 percent ready. It's an unbelievable city. I'm very proud of our city," Paes said Monday at the presentation of a new bus expressway, part of an overhaul to the overburdened transportation system.

Some 10,000 athletes will compete over 19 days in Rio, ranging from familiar sports icons such as sprinter Usain Bolt and swimmer Michael Phelps to the stars of Olympic newbie sport rugby sevens and golf, which returns after more than a century's absence.

But despite growing excitement in the sporting world and the visible transformation of Olympic sites in Rio, a mounting series of problems are overshadowing the Games.

The authorities will deploy 85,000 police backed by soldiers on Rio's streets. That's twice as many as used in the 2012 London Olympics.

Terrorism is a serious concern after the Islamic State group demonstrated its geographical reach, with bombings in Istanbul and Baghdad blamed on the group in the last few days.

Brazil's distance from jihadist hot spots, coupled with the country's absence from wars, is expected to be the main factor on security forces' side.

However, Rio already faces its own serious violent crime that has embarrassed Olympic organizers trying to change the city's image.

Although down from horrific levels a decade ago, the murder rate is on the rise and street crime is also proliferating, symbolized by the hijacking of a truck filled with German television equipment last week.

Police -- heavily criticized by human rights groups over their brutal tactics in slums known as favelas -- are themselves coming under deadly fire. More than 50 Rio state