(Marcos) Arturo Beltrán Leyva (September 27, 1961 – December 16, 2009) was the leader of the Mexican drug trafficking organization known as the Beltrán-Leyva Cartel, which is headed by the Beltrán Leyva brothers: Marcos Arturo, Carlos, Alfredo and Héctor. The cartel is responsible for cocaine, marijuana, heroin and methamphetamine production, transportation and wholesaling. It controls numerous drug trafficking corridors into the United States and is also responsible for human smuggling, money laundering, extortion, kidnapping, murder, contract killing, torture, gun-running and other acts of violence against men, women, and children in Mexico. The organization is connected with the assassinations of numerous Mexican law enforcement officials.
Since the mid 1990s Arturo Beltrán Leyva allegedly led powerful groups of assassins to fight for trade routes in northeastern Mexico. By 2008, through the use of corruption or intimidation, he was able to infiltrate Mexico's political, judicial and police institutions to steal classified information about anti-drug operations, and even infiltrated the Interpol office in Mexico.
The Beltrán Leyva brothers, who were formerly aligned with the Sinaloa Cartel, are now allies of Los Zetas.