RIO DE JANEIRO (AFP) Rio de Janeiros image of fun and sun that helped it win the 2016 Olympics has been marred by a resurgence in drug-related violence that raises questions over the citys preparedness. Pictures of a downed police helicopter in flames in one of Rios numerous slums were sent around the world a week ago as media highlighted the defiance shown to authorities and the big task they face. Although President Luiz Inacio Lula da Silva vowed to clean up the problem of drug-trafficking gangs, and hundreds of Rio police deployed to the slums, the violence continued through the week, leaving a death toll of at least 33. The International Olympic Committee, though, reiterated its confidence in Rios ability to host the Olympic Games. It pointed out that in July 2005 London was hit by bomb attacks on its public transport system that left 52 dead the day after it won the right to hold the 2012 Olympics. Nevertheless, doubts remain over Brazilian authorities capacity to rein in its chronic urban unrest in a city when a third of its six million inhabitants live in more than a thousand slums. The rival power of the drug gangs is exploding the pillars of the republic. For how much longer? asked the head of Brazils lawyers association, Cezar Britto. There are around 6,000 homicides a year in all the state of Rio, which has a population of 14 million. That figure is 10 times higher than for New York, or eight times that of all of France. Since 2007, homicides have fallen from 45 per 100,000 inhabitants to 33, the head of security for the state, Jose Mariano Beltrame, told AFP. Our aim to is to bring crime down to tolerable levels, like those in industrialized countries, he added. A police pacification operation has already been underway for a year in five slums, which have permanent patrols. Big investment has also poured to transform the most violent shantytowns, in a program that is to be extended to around 100 of them by 2016. Thus far, though, the pacification effort has mainly seen the drug traffickers simply move to other slums. The police retake territory occupied by the traffickers, and theres a violent reaction on their part, a professor at Rio Universitys Violence Studies Center, Alba Zaluar, told AFP. She explained that Brazils vast and poorly monitored borders made it easy for criminals to bring in arms and drugs. Compounding the problem is the fact that Rios police are poorly trained, badly paid and often corrupt. Only a cooperation between the police and the military can improve the situation, she said. There are three types of police forces in the country: the federal police, the military police and the civil police. They are present in all of Brazils 27 states. Lula in 2002 promised to reform the constitution to merge the civil and military branches, but that has gone unfulfilled, and the president has just over a year left before he has to step down to make way for an elected successor.