(Updates with injury report, more details.)
A fireworks factory located on one of the main routes into Bogota from the south exploded on Sunday, slightly injuring one person, Colombian media reported.
Firefighters responded to a huge blaze caused by the blast.
The explosion slightly injured a driver who was passing nearby at the time. He was treated on the scene for superficial shrapnel wounds on his right arm, after which he continued on his way, the Crue emergency center of Cundinamarca province said.
The blast occurred at 10:00 a.m. near Granada, just off the highway that links the city of Girardot with Bogota.
Fire trucks from nearby cities arrived to fight the blaze sparked by the explosion, which forced officials to close the highway in both directions.
The road closing created a huge traffic jam as people return to the capital from New Year's vacations outside the area.
Authorities said that five warehouses where gunpowder was being stored were destroyed in the blast and fire, and numerous additional explosions were heard while the fire raged.
Cundinamarca provincial fire department Capt. Ivan Dario Valenzuela told local media that the situation had been "80 percent" brought under control and provincial Gov. Alvaro Cruz said that an investigation had been launched to determine why the factory blew up, although he said it appeared the facility had all its permits to store and sell gunpowder in order.
The explosion occurred near a restaurant complex frequented by travelers using the highway to return to Bogota, media reports said.
Police were directing drivers to use other highways and officials offered alternative routes to travelers via the media. EFE