Intelligence officials intercepted a 12-kilo bomb allegedly meant to be detonated at a military base in the city of Cali.
According to the director of intelligence agency DAS, the bomb was found in a bus that had come from the town of Suares in the south-western Cauca department.
Police investigators estimate that the bomb was big enough to cause serious damage within a 100-meter radius.
DAS director Felipe Muñoz was quoted as saying by newspaper El Tiempo that the bus driver was instructed to drive up to the military aviation school Marco Fidel Suarez, but was stopped by police before arrival.
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