In early 1907, lawyer Enrique Ávila Echeverría and his brother, physician Jorge Ávila Echeverría, along with Dr. Julio Valdés Blanco and electrical engineer Baltasar Rodil, planned a bombing attack on the president of Guatemala, Estrada Cabrera, which took place on April 29, 1907 and is generally known in Guatemala as "The Bomb". The Echeverría brothers and their confederates were members of the elite class and had studied abroad, but when they returned to Guatemala, they objected to the government's extreme abuse of power and determined on assassinating the president. They decided on explosives. They prepared everything meticulously: the explosives, the detonators, the day and the exact time; even the president's driver—Patrocinio Monterroso—was part of the conspiracy.