Dozens of narcotics police seized more than 1,500 pounds of partially processed cocaine after a jungle shootout in which two traffickers were killed and four wounded, officials reported Friday.

The U.S. Embassy said U.S. helicopters ferried Peruvian police, but neither the aircraft nor U.S. Drug Enforcement Administration agents were present during the fight.Police said the 1,570 pounds of cocaine base, which can be refined into an an approximately equal quantity of pure cocaine, was one of the largest single seizures of the drug in Peru.

They said the raid took place Thursday at an airfield on the outskirts of Uchiza in the cocaine-producing Huallaga Valley, about 265 miles northeast of Lima.

Officials said police moved in while traffickers were loading the drugs on a plane.