Latin America emerged in 2015 as a less peaceful region than it was the year before, according to a new study on global peace released Wednesday. The general trend is driven by increasing social unrest and instability in Venezuela and Brazil and buoyed by consistently high levels of violent crime in Central American countries.

The Global Peace Index, which gauges peace levels by measuring intensity of conflicts, pervasiveness of crime and violence and availability of weapons, issued its 2015 report Wednesday, showing that South America’s overall peace score dipped below the global average this year. Latin America as a whole remained the most violent region in the world -- outside of conflict zones -- based on homicide rates and personal safety.

Brazil, Venezuela and Colombia were the lowest-ranked countries in South America, with Brazil’s and Venezuela’s peace scores both falling slightly from the year before. Venezuela saw an increased risk of “violent demonstrations, violent crime and political instability as the economic crisis has deepened and anti-government sentiment has risen,” the report said. The 2015 index was based on research conducted from March 2014 to March 2015 and undoubtedly took into account the mass street demonstrations that rocked Venezuela for two months last year and resulted in more than 40 deaths. Demonstrations have continued sporadically since then, with the most recent one taking place May 30.

Political instability and an increased likelihood of violent demonstrations accounted for Brazil’s low score as well. Anti-government sentiment has risen there in the wake of President Dilma Rousseff’s handling of a massive bribery and kickback scheme in the state-run energy company. The scandal began overtaking national headlines last year and has prompted some opposition supporters to mount calls for Rousseff’s ouster.

Colombia was one of the region’s least peaceful countries, ranking 146 out of 162 countries in the world. The report attributes this to Colombia’s outflow of refugees and displaced persons, stemming from the government’s conflict with guerrilla groups.

Chile, meanwhile, remained the most peaceful country in the region. Scores in Ecuador and Peru also improved thanks to declining internal conflicts, the report said.

In Central America and the Caribbean, the three so-called Northern Triangle countries – Honduras, El Salvador and Guatemala – were ranked among the lowest in the region, likely due to consistently high levels of violent crime. All three countries have among the highest homicide rates in the world, which have fueled a mass exodus of unaccompanied children and families north to Mexico and the United States in recent years. This year, El Salvador has been seeing historic homicide rates in the aftermath of a broken gang truce.

Mexico ranked last out of Central American and Caribbean countries due to ongoing conflicts in the drug war, but its peace score actually improved from the year before. “The government of Enrique Peña Nieto has eased off a bit, compared with his predecessor [Felipe Calderon], in terms of aggressive tactics against drug cartels,” the report said.