Rio de Janeiro (AFP) - Homicides surged this year in Rio de Janeiro state despite increased security for the Olympics, but fell in Brazil's economic hub Sao Paulo, statistics showed Friday.

In Rio state, whose capital city hosted the Summer Olympics in August, there were 4,572 homicides through the end of November -- an increase of 19.7 percent from 2015, according to the Public Security Institute.

But Sao Paulo, the country's economic hub and most populous state, was trending in the other direction.

It registered 3,313 homicides, down more than eight percent from 2015 and the lowest figure since 2001, the state's public security secretariat said in a statement.

Both states and their capital cities are hotspots in Brazil's fight against powerful drug gangs, which has made the country one of the most violent in the world.

One expert, Alba Zaluar, attributed the two states' divergent homicide numbers to a proliferation of turf wars between drug gangs in Rio and a relative peace in Sao Paulo.

"In Sao Paulo, violence has declined the past several years. A single organized crime faction dominates everything: the PCC (First Capital Command). Additionally, since 2006 there has supposedly been a deal between the PCC and the state government," said Zaluar, an urban anthropologist at Rio de Janeiro State University.

"In Rio, we have three organized crime factions. And now the PCC has broken its truce with the CV (Red Command, a rival gang)," she told AFP.

The bloodshed in Rio came despite the deployment of 85,000 police and soldiers for the Olympics.

Homicides claimed more lives in Brazil from 2011 to 2015 than the Syrian civil war during the same period, according to the Brazilian Public Security Forum: 278,839 for Brazil, against 256,124 in Syria.