Born in Mexico City, the offender allegedly ordered the execution of the deputy prosecutor in Guanajuato, Jesus Bautista Arambula, November 15, 2012, and was in charge of police officers in Uruapan, Michoacan.

From 2002 to 2004, besides being the municipal police commander in that municipality, he worked in the ministry, secretary of transportation.
In 2007, Cornejo Tello "El Pelon" or "El Tello" was arrested in Michoacan in possession of drugs and guns, and was incarcerated in the prison of Charo, in the same state.
The Attorney General of the State of Guanajuato confirmed this afternoon that the alleged leader of the Knights Templar in the Guanajuato is associated with the collection and sale of stolen fuel from Petroleos Mexicanos.
"He controlled the clandestine sale of oil in the state and charged extortion fees to so-called 'huachicoleros,' vendors of clothing, pirated discs, and semi-fixed positions in flea markets, restaurateurs and bar owners in various municipalities. He participated in the commission of several kidnappings, perpetrated extortion of all traders of all lines of business established in Yuriria, Moroleón and Uriangato." said the agency in a statement.
"El Pelon" had influence in León, Salamanca, Celaya, Irapuato, Valle de Santiago, Apaseo El Alto, Yuriria, Moroleón and Uriangato.
The alleged offender was presented this afternoon before the press at the state office of the Attorney General's Office for drug crimes, illegal possession of weapons unique to the armed forces and the killing of the deputy prosecutor.
