Mexican marines unearthed 15 bodies in two mass graves in Veracruz. Authorities were led to the graves by a suspected member of the Los Zetas cartel, one of Mexico's most powerful and most violent drug gangs.

The bodies, which were found in an advanced state of decomposition, were buried on a ranch in the town of Acayuan in Veracruz state, according to reports.

The suspect, Juan Francisco Alvarado Martagon, was apprehended while trying to evade a police checkpoint. Martagon, who goes by the nickname El Pollo H, admitted to be being a leader in the Zetas' falcons division and said he helped kidnap a number of rivals.

Mass graves have become a fixture of the drug war in Mexico. An estimated 17,000 people were killed from drug-related violence in 2010 alone, some of those during shoot-outs with law enforcement and military offices, but many others were killed by the hands of the cartels.

Hundreds of bodies have been found in mass graves across the country over the past few years, including in the tourist-friendly Acapulco, the violence-riddled border city of Ciudad Juarez, and inside a cargo truck in Mexico City.

The Zetas are currently in the midst of a war with the Sinaloa Federation cartel. The two represent the biggest and wealthiest of all the cartels in Mexico, and they control the east and west coasts of the country respectively.

Veracruz, which sits on the Gulf of Mexico, is quickly becoming one of Mexico's bloodiest states. As police and army troops were dispatched to the region, a new cartel, the Jalisco Nueva Generación, appeared. Calling themselves the “Mata Zetas, or “Zeta killers,” the cartel allied with Sinaloa last year and has been fighting for control of the state.

The cartels are also fighting against the government. President Felipe Calderon launched an offensive against the drug gangs after his election in 2006 and has mobilized the army and navy in an effort to crush the drug trade.

About 45,000 Mexican troops -- a quarter of the country's military personnel -- are involved in the campaign. Since most of the narcotics head north, the United States provides funding and Drug Enforcement Administration (DEA) agents for Calderon's battle.

Since Calderon's crackdown began, about 50,000 people have been killed from drug-related violence. Additionally, the number of annual deaths has steadily increased in each of the past five years. There were between 12,000 and 13,000 drug-related killings between January and September 2011, which was almost three times as many as during the same period in 2009 and 2008.