Marlon, whose real name is Iván Jacob Idrobo Arredondo, is suspected of ordering Saturday's bomb attack that killed 20 people. This attack is one of the deadliest targeting civilians and occurs just over a month before the presidential election scheduled for May 31. Sánchez said the $1.4 million reward for Marlon is the largest ever offered by Colombia. The defense minister accused Marlon of being behind Saturday's attack, as well as a series of others in the provinces of Cauca and Valle del Cauca in southwestern Colombia over the weekend. No evidence or details were released, according to the BBC. In the deadliest of these incidents, 15 women and five men were killed when an explosive device was detonated on a highway connecting the cities of Cali and Popayán, said the governor of Cauca province. The explosion destroyed several buses and other vehicles and created a massive crater. Marlon belongs to an armed group led by a dissident rebel known by the pseudonym Iván Mordisco, the most wanted person in Colombia. Mordisco was once part of the Revolutionary Armed Forces of Colombia (FARC) but broke away from the rebel group while it was negotiating a peace agreement with the government in 2016. He is considered the most powerful dissident rebel leader in Colombia. His group is involved in illegal mining, extortion, and drug trafficking. Cauca Governor Octavio Guzmán described Saturday's explosive attack as the most brutal and reckless assault on civilians in recent decades.