TEHRAN, Young Journalists Club (YJC) - The defense ministry said the "terrorist act" was carried out using a vehicle packed with 80 kilograms (around 175 pounds) of explosives.
"Unfortunately, the preliminary toll is 21 people dead, including the person responsible for the incident, and 68 wounded," Colombian police said in a statement, adding 58 of those injured had been discharged from hospital. The defense ministry had previously reported 11 dead and 65 injured.
"All Colombians reject terrorism and we're united in fighting it," President Ivan Duque tweeted in the aftermath.
Later in a statement to the nation, he said he had ordered reinforcements to Colombia's borders and routes in and out of cities.
"I have also requested that priority be given to all the investigations ... to identify the masterminds of this terrorist attack and their accomplices," he said.
The bomber -- who authorities confirmed was killed in the attack -- struck at the General Francisco de Paula Santander Officer's School in the south of Bogota during a promotion ceremony for cadets.
No group has claimed responsibility, but public prosecutor Nestor Humberto Martinez named suspect Jose Aldemar Rojas Rodriguez as the "material author of this abominable crime."
Martinez said Rojas Rodriguez entered the school compound at 9:30 am (1430 GMT) driving a grey 1993 Nissan Patrol truck, but gave no details about the explosion.
He said the truck underwent an inspection in July in the Arauco department on the border with Venezuela -- a traditional stronghold of ELN Marxist guerrillas.
Source: AFP