In a raid on a rural drug refuge, the army arrested more than 100 alleged traffickers, seized about 1,900 pounds of pure cocaine, discovered huge coca fields and destroyed laboratories, an army official said. The cocaine seized in Monday's operation near Colombia's northern coast was hidden among cargo bags and ready to be exported to the United States, said regional army commander Col. Carlos Castro. He said troops destroyed six cocaine-processing laboratories, arrested 103 suspected drug traffickers and found nearly 5,000 acres of coca leaf, the raw material used to make cocaine. Soldiers also seized 30 vehicles, all with Venezuelan license plates, which had been used to transport drugs, Castro said. Also confiscated were cocaine- processing chemicals and a cache of weapons, he said. The bust was considered one of the year's most important. So far in 1990 security forces have confiscated about 45 tons of cocaine, compared to 33 tons in all of 1989. Colombia's Medellin and Cali cocaine cartels supply most of the cocaine consumed in the United States. The coca leaf is mostly grown in Bolivia and Peru, then processed in Colombia. The Medellin cartel has been blamed for a long series of terrorist attacks in which at least 550 people have died in the past 14 months.