claim: Shomu Mukherjee died on April 1, 2008.
evidence: The infighting in Los Zetas referred to confrontations between two factions in that criminal organization , Mexico 's most violent , one led by Heriberto Lazcano Lazcano , alias El Lazca and the other led by Miguel Trevino Morales , alias Z-40 .. Los Zetas. Los Zetas. Heriberto Lazcano Lazcano. Heriberto Lazcano Lazcano. Miguel Trevino Morales. Miguel Trevino Morales. The rumors of the split appeared in mid-2012 , when public banners and music videos on the web alleged betrayals between the two leaders .. After the death of Lazcano it was confirmed that the leaders were not confronting each other , but rather that some men within Morales ' faction did not want him as leader .. The split of Los Zetas began in 2010 , when a regional leader of the organization disobeyed orders and killed 72 illegal immigrants and nearly 200 people in the northeastern Mexican city of San Fernando , Tamaulipas .. Los Zetas. Los Zetas. 72 illegal immigrants. 2010 San Fernando massacre. nearly 200 people. 2011 San Fernando massacre. In August 2011 , several low-level Zeta members went into a casino in northern Mexico and set the place on fire .. In the attack , which was a retaliation for the owner 's failure to pay for `` protection '' , 52 people were killed .. 52 people were killed. 2011 Monterrey casino attack. The massacre was among the deadliest in Mexico 's drug war and brought attention from the government .. The mastermind of the attack turned out to be a mid-level leader who had carried out the attack without the approval of the top echelon .. In mid-2012 , a regional cell disobeyed Morales ' commands and dumped 49 decapitated bodies on a roadside ; Morales had ordered his henchmen to abandon the bodies in a city 's main square and not outside the city limits .. 49 decapitated bodies. Cadereyta Jimenez massacre. Unlike other traditional criminal organizations in Mexico , a large portion of Los Zetas income comes from local operations .. Los Zetas. Los Zetas. Drug trafficking makes up at least 50 % of their revenue -LRB- other sources say less -RRB- .. The Zetas were more prone to activities such as kidnapping , extortion , theft and piracy .. This decentralized structure opened the gang to internal splits , given the influence of low-level and regional leaders .