Heraldo de Madrid - Colombia road bombing death toll rises to 20

The attack -- which local and national officials are blaming on armed groups -- comes one month before the country holds presidential elections on May 31.

Cauca Department Governor Octavio Guzman described the bombing as the area's "most brutal and ruthless attack against the civilian population in decades," adding that it left a crater 200 cubic meters in size.

Fifteen women and five men, all adults, were killed, he said. Of the injured, three people remain in intensive care. Five children were also injured but "are out of danger."

The massive blast left buses and vans mangled on the Pan-American Highway in the restive southwestern region of Colombia.

Several cars were flipped over by the force of the explosion.

Military chief Hugo Lopez told a news conference on Saturday that the bomb had exploded after assailants stopped traffic by blocking the road with a bus and another vehicle.

"It is a terrorist attack against the civilian population," Lopez said.

The attack comes just over one month ahead of national elections, in which voters will pick a successor to leftist President Gustavo Petro.

"Those who carried out this attack... are terrorists, fascists and drug traffickers," Petro said on X. "I want our very best soldiers to confront them."

Petro blamed the bombing on Ivan Mordisco, the South American country's most-wanted criminal, whom the president has compared to late cocaine kingpin Pablo Escobar.

The violence came after a bomb attack Friday on a military base in Cali, Colombia's third-largest city, injured two people and set off a string of attacks in the Valle del Cauca and Cauca departments.

According to Lopez, 26 attacks have been recorded in the two departments over the past two days.

Authorities have boosted military and police presence in the areas, Defense Minister Pedro Sanchez said Saturday.

Colombia has a history of armed groups -- which finance their operations through drug trafficking, illegal mining and extortion -- attempting to influence elections through violence.

FARC remnants who rejected a 2016 peace deal with the government have been actively trying to disrupt stalled peace talks with Petro.

Security is one of the central issues of the presidential election. Political violence was brought into sharp focus last June, when young conservative presidential frontrunner Miguel Uribe Turbay was shot in broad daylight while campaigning in the capital Bogota. He died two months later.

Leftist Senator Ivan Cepeda, an architect of Petro's controversial policy of negotiating with armed groups, is ahead in polls.

He is trailed by right-wing candidates Abelardo de la Espriella and Paloma Valencia, both of whom have pledged to take a hard line against rebel groups.

All three have reported receiving death threats and are campaigning under heavy security.

A.Montoya--HdM