Plainclothes police officers stand guard as people with missing relatives search a cemetery in Torreon, in the Mexican state of Coahuila February 21, 2015. For the past two months, relatives of missing people in the Mexican city of Torreon have met every Saturday to personally look for missing relatives after the city was severely hit by an increase in murders, due to an intense struggle between rival drug gangs. The Zetas cartel arrived in Torreon in mid-2007 and started battling against the Sinaloa cartel for control over this centre of manufacturing, mining and farming once seen as a model for progress, which then became one of Mexico's most dangerous cities. Picture taken February 21, 2015. REUTERS/Daniel Becerril (MEXICO - Tags: CIVIL UNREST CRIME LAW DRUGS SOCIETY)