Police in Colombia accused the Marxist terrorist National Liberation Army (ELN) of killing 21 people and injuring dozens in a car bombing in the capital city, Bogotá, on Thursday.

The blast took place outside the General Santander police academy in Bogotá at around 09:30 on Thursday morning.

The incident began when a grey Nissan Patrol, loaded with the 80kg (176lb) of the powerful explosive pentolite, entered the compound as a promotion ceremony for cadets was taking place. When guards stopped the vehicle for a routine security check, the driver accelerated and drove the car into a wall, setting off an explosion that shattered the windows of nearby apartments and houses.

#Atención El alcalde @EnriquePenalosa se encuentra en la Escuela General Santander acompañando a la @PoliciaColombia. En breve entregaremos más información.#BogotáCondenaElTerrorismo pic.twitter.com/HBekT48yYi — Alcaldía de Bogotá (@Bogota) January 17, 2019

The main suspect behind the attack is 57-year-old José Aldemar Rojas Rodríguez. Early indications suggest he was a member communist terrorist organization National Liberation Army (ELN). According to El Tiempo, the suspect had no prior previous criminal record and had been living in the northern department of Boyacá, where the ELN is based.

In his address to the nation on Thursday, President Iván Duque described the attack as a “crazy terrorist act” and declared three days of national mourning.

“The Cadet school General Santander suffered a miserable terrorist attack that claimed the lives of first-year cadets and left other young people injured on the way to becoming policemen,” he said. “The country accompanies their families in their grief. This despicable act will not go unpunished.”

La Escuela de Cadetes General Santander sufrió un miserable ataque terrorista que cobró la vida de cadetes de primer año y dejó heridos a otros jóvenes en camino de convertirse en policías. El país acompaña a sus familias en su dolor. Este despreciable acto no quedará impune. pic.twitter.com/2YpISTb3dN — Iván Duque (@IvanDuque) January 18, 2019

The attack will have come as a troubling sign to many Colombians of a possible return to the communist violence that has plagued the country over recent decades.

In 2016, former President Juan Manuel Santos signed a widely unpopular peace agreement with the Revolutionary Armed Forces of Colombia (FARC) designed to bring an end to the country’s longstanding civil war. The deal has done little to stem the flow of violence as other communist terrorist groups have grown in size and indications suggest the FARC, despite now being recognized as a legitimate political party, continues to engage in violence and drug trafficking.

Last year, a similar attack took place at a police station in Barranquilla, Colombia, killing five officers and wounding 41 others.

Duque, elected last June as the successor to former hardline anti-communist President Álvaro Uribe, pledged to continue a crackdown on armed groups by targeting their ringleaders, their property, and their funding.

“We will continue to act against organized armed groups,” he said “We will deepen the reward systems to capture their ringleaders and extinguish the dominion of all their property without any contemplation. We will pursue their funding sources.”

“It’s an attack on society,” he added. “Colombians have never yielded to terrorism, we have always defeated it. This will not be an exception.”

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