At least eight people were killed and another 10 injured in a car bombing at a police academy in Colombia's capital on Thursday, authorities said.
The scene outside the General Santander police academy in southern Bogotá was chaotic in the immediate aftermath of the explosion, with ambulances and helicopters rushing to the normally tightly controlled facility.
Witnesses said they heard a loud blast that destroyed windows in adjacent apartment buildings. Pictures on social media showed a charred vehicle surrounded by debris on the academy's leafy campus.
Bogotá Mayor Enrique Peñalosa said at least 5 people were killed and 10 injured.
President Iván Duque said he and his top military commanders were rushing back to the capital from a visit to a western state to oversee police investigation into what he called a "miserable" attack.
"All of us Colombians reject terrorism and are united in confronting it," Duque said in a tweet. "We won't bend in the face of violence."
For decades, residents of Bogotá lived in fear of being caught in a bombing by leftist rebels or Pablo Escobar's Medellín drug cartel. But as Colombia's conflict has wound down, security has improved and attacks have become less frequent.
While authorities had yet to suggest who was behind the attack, attention was focused on leftist rebels from the National Liberation Army, which has been stepping up attacks on police targets in Colombia amid a standoff with the conservative Duque over how to re-start stalled peace talks.
The group known as the ELN was long considered a lesser military threat than the Revolutionary Armed Forces of Colombia, whose 7,000 guerrilla fighters disarmed as part of a 2016 peace accord. But in the wake of the peace deal the Cuban-inspired insurgency has been gaining strength, especially along the eastern border with Venezuela, where it has carried out a number of kidnappings and bombings of oil pipelines that have hardened Duque's resolve in refusing to resume peace talks stalled since he took office last August.
Thursday's bombing was the deadliest in the capital since an explosion at the upmarket Andino shopping mall in June 2017 killed three people, including a French woman, and injured another 11. Police later arrested several suspected members of a far-left urban guerrilla group called the People Revolutionary's Movement for the bombing.