epa-efeCali, Colombia

An explosion of unknown origin rocked a regional branch of the Colombian Attorney General's Office Friday in this southwestern city, authorities said.

The Cali police commander, Gen. Hugo Casas, told CM& television that the explosion appeared to be the result of an accident in an evidence-storage area.

Terrorism is not suspected at this point, he said.

The blast took place in a 15-story structure near the building housing the administration of Valle del Cauca province.

"We have no report of injuries so far," Casas said.

The "conflagration" that followed the explosion was brought under control by firefighters, the police chief said.

Cali Mayor Maurice Armitage said that the blast apparently resulted from the "mishandling of explosives" stored in the building.

Television images showed several fire trucks spraying water at the building's second floor.