MANAUS — There's a gang war raging across northern Brazil. It has led to prison riots in which close to 100 inmates have been killed since the beginning of the year. This violence is linked to the flow of cocaine from Peru to Brazil's northern, northeastern and central-western regions. The money involved is huge — billions annually — according to official data collected by the state of Amazonas from 10 Brazilian states.

The main players in this war include top South American crime syndicates: Northern Family ("Família do Norte" or FDN) allied with Red Command ("Comando Vermelho" or CV), against First Capital Command ("Primeiro Comando da Capital" or PCC).

PCC appears to control the most territory, with a reported presence in seven of the states that data was collected from, as opposed to the six states CV has a hold in and two which FDN operates in. Many of these states are also home to local factions. Of the 10 states featured in the report, only two (Góias and Rio Grande do Norte) told Amazonas authorities they knew of no criminal gangs in their territory.

In Amazonas, a state that shares more than 3,000 kilometers of border with Peru, all three main gangs are present. The biggest organization in this vast state is FDN, which was actually founded in the state's capital city of Manaus, and which controls most of the drug business. Meanwhile, its rival PCC controls the supply routes from Bolivia, from where Peruvian and Bolivian cocaine pour into Brazil's central-southern region.

In both cases, the main and final destination is the Brazilian market, the report says. Brazil indeed ranks second in cocaine consumption, second only to the U.S., according to a UN study published in 2015.

Brazil's federal police estimate that there are as many as 10,000 hectares of coca plants in Peru near the border. No wonder then that the report by Amazonas estimates $4.5 billion in annual profit from the drug trade. This figure doesn't even include cocaine from Colombia, which enters the country in smaller quantities and about which there's little information.

"The results obtained indicate that the state of Amazonas being both on the border with Peru and Colombia, is the main corridor from where cocaine enters Brazil," the report notes.

The document also says that the current number of police and military officers isn't enough to fend off the intense drug trafficking activity in Amazonas and recommends that their numbers should at least be doubled.

After the report's release, the secretary of public security at Amazonas, Sérgio Fontes, warned that without change, "we're on the path to become Mexico."