Brazil has stepped up security in Rio de Janeiro amid a spike in violence by organized crime.

Thousands of troops have been sent to patrol Brazil’s second largest city as authorities admit the situation is out control.

CGTN’s Lucrecia Franco reports from Rio.

Follow Lucrecia C. Franco on Twitter @LucreciaFranco

Just a year after Rio hosted the first-ever Olympic games in South America, soldiers are patrolling the streets in one of Brazil’s most beautiful cities.

The troops deployed to Rio are lending a hand in the fight against criminal gangs involved in drug trafficking, cargo theft, robbery and murder.

According to Defense Minister Raul  Jungmann, drug gangs dominate many of the city’s slums.

“Around eight hundred communities are under siege, where individual constitutional rights are worth nothing, because criminals are in control,” Jungmann said.

Shootouts between rival gangs and the police jumped 50 percent from January to June, leaving nearly 600 people dead – including 90 police – so far this year.

The military operation in Rio is scheduled to run until the end of the year, but it could be extended until 2018.

Critics said there’s no guarantee the operation will bring a lasting solution, but Robert Muggah, director of security think tank Igarape Institute, believes the current approach has the potential to work better than past attempts.

“The minister of defense has announced they will have a more integrated approach with the military and civil police,” according to Muggah. “They’ll be intelligence led, and they are going to focus on organized crime. If they follow through with this objective, then we might actually see a more positive outcome this time around.”

Many citizens, however, remain worried about what will happen when the soldiers are gone.