A bomb carried by a cyclist exploded as he rode past a park full of children celebrating Halloween, leaving two people dead and 27 children injured, police said.
The man with the bomb may have been targeting a nearby police station in Pradera in southwest Colombia, said Carlos Leyton, a spokesman for the Pradera city government.
The bomber in Wednesday's night's blast was apparently included among the fatalities, Leyton said.
Two children were seriously hurt and 25 suffered slight injuries, he added.
He said the bomber's motives were not immediately clear, nor was it known if he belonged to an illegal organisation.
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