On Thursday, a car bomb broke through a checkpoint near the police school building at exploded in its premises. According to media reports, 11 people have been killed and 87 others injured in the attack.
"To honor their memory, we have announced three-day national mourning," Duque said in a televised address to the nation.
The president also ordered to tighten security measures at the country's border and routes leading to cities. Duque called on Colombians to unite against terror threat and asked them to support the investigation into the attack.
Duque said the authorities had identified the perpetrator on the day of the attack and were eager to bring the people connected to the terror act to justice.
The president pledged to boost fight against criminal gangs and reconsider the system of remuneration for capturing their heads.
The Heraldo news outlet reported that the authorities had already identified six out of 11 people injured in the attack.
The Colombian authorities have reportedly identified the perpetrator of the attack as Jose Aldemar Rojas Rodriguez, 56, who died in the incident.
The Tiempo news outlet reported, that the authorities were looking into Rojas' links to Colombian insurgent groups the Revolutionary Armed Forces of Colombia (FARC) and the National Liberation Army (ELN).
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