"A coward terrorist attack in Centro Andino hurts me." Penalosa wrote on Twitter.
"I regret to report that there are 3 women killed in bomb explosion at Centro Andino. Another one is in serious condition, but not at risk of death," Penalosa also wrote.
The mayor added among those killed there was 23-year old French national Julie Huynh, who had been working in Colombia as volunteer for six months.
— BluRadio Colombia (@BluRadioCo) June 17, 2017
According to media reports, the blast occurred in a toilet room on the second floor of the mall. Following the explosions, the evacuation of people was launched.
Colombian President Juan Manuel Santos expressed his solidarity with the victims and ordered an investigation into the matter.