More than 22,700 people have been killed in Mexico's drug war since a U.S.-backed military crackdown on cartels began more than three years ago, according to a government report.
The report said 2009 was the deadliest year in the drug war, with 9,635 people killed in violence tied to organized crime. That compares to 2,837 in 2007, the first year of President Felipe Calderon's military-led offensive.
Gang violence has continued surging this year, with 3,365 people killed between January and March, according to the confidential report sent to lawmakers Monday. The Associated Press had access to the report Tuesday.
In the latest violence, the bodies of six men were dumped on the side of a highway in Cuernavaca, a city near Mexico's capital where authorities say a battle has erupted for leadership of the Beltran Leyva cartel, whose leader was killed in a shootout with marines in December. Police said the six men were tortured, then each shot once in the head.
In northern state of Tamaulipas, which borders Texas, gunmen burst into a bar and killed eight people Monday night, the state government said. Five died inside the bar in the town of Los Guerra and three were chased down and killed as they tried to flee in car.
Tamaulipas has become the newest front in Mexico's drug war amid a split between the Gulf cartel and its former gang of hit men, the Zetas.
Has crackdown led to abuses?
Calderon's U.S.-backed deployment of more than 40,000 soldiers and federal police across the country has come under increasing criticism from opposition politicians and drug trade experts, who argue the crackdown has led to human rights abuses and done little to stem the flow of narcotics to the U.S.
The government attributes the increase in violence to gangs lashing back at security forces and infighting among cartels whose leadership has been shaken by the arrest of top kingpins.
More than 121,000 drug suspects have been detained since 2006, the report said. It gave no figure for how many of those had been convicted.
The report said more than half those arrested were from the Gulf and Sinaloa cartels, Mexico's two most powerful gangs. Some 27 percent were from the Gulf cartel or the Zetas, two groups that Mexican and U.S. authorities say recently split. About 24 percent were tied to the Sinaloa cartel, led by Joaquin "El Chapo" Guzman, Mexico's most-wanted drug lord.
Since Guzman escaped from prison 10 years ago, successive Mexican governments have faced accusations that his organization is not pursued as aggressively as other gangs. Calderon denies the charges.
Among the Sinaloa suspects arrested have been a son and nephew of Ismael "El Mayo" Zambada, who authorities say runs the cartel along with Guzman.
Gang bosses at large
But most of the gang's top leaders remain large, while several bosses of rival gangs have been brought down, including Arturo Beltran Leyva, the kingpin killed the December shootout in Cuernavaca.
U.S. officials say the Sinaloa cartel has grown to become the most powerful drug trafficking group in the world. Most recently, it is said to have won a two-year battle with the Juarez cartel for control of smuggling routes through Ciudad Juarez, a border city that has become one of the world's deadliest.
The government report said 4,324 people have been killed since 2006 in Ciudad Juarez, a city of 1.3 million people.
Chihuahua state, where Ciudad Juarez is, was Mexico's hardest-hit state, with 6,757 people killed in gang violence since 2006. Sinaloa, a stronghold of Guzman's cartel, followed with 3,136 deaths. Guerrero, home to the Pacific coast resort of Acapulco, was third with 1,826.
The report indicated security forces have been involved in most of the gunbattles of the past three years: 977 shootouts have been between gangs and security forces, compared to 309 between rival gangs.