Michoacan, a mountainous, agricultural state in western Mexico, has been ravaged by fighting between drug gang henchmen and vigilantes who took up arms against the cartels but have since splintered into violent factions. A mid-December shootout between two rival groups that killed 11 people has reignited fears the government is failing to control the state after flooding it with federal troops and pressing vigilantes into a fledgling rural police force. The renewed fighting in Michoacan comes [just after] the apparent murder of 43 trainee teachers by a drug gang working with corrupt police in neighboring Guerrero state. The incident sparked widespread protests against the government, compounded by conflict-of-interest scandals enveloping the president and his finance minister. Pena Nieto discussed Mexico's chronic violence with US President Barack Obama in Washington on Tuesday. The main gangs operating in Michoacan ... were founded by Nazario Moreno. On local television, Alfredo Castillo, Michoacan's federal security commissioner ... said there were various testimonies indicating heart-eating was part of a macabre initiation Moreno used to root out moles or test his men's loyalty. More than 100,000 people have been killed in gang-related violence in Mexico since 2007.