Afghan officials say counternarcotic teams have seized some 21 tons of heroin and morphine.
The bust, the biggest of the year, was made during a helicopter raid with the help of Russia's Federal Drug Control Service.
General Abdul Khalil Bahktyar, the raid commander, said in a news conference in Kabul on March 12 that Afghan commandos raided a facility in the Sherzad district of Nangarhar Province.
The drugs seized included large quantities of chemicals such as ammonium chloride, which is used to manufacture illicit drugs.
Bahktyar said the raid was the latest of about 200 carried out this year.
He said the narcotics seized were burned at the scene and six drug labs destroyed.
Afghanistan produces about 90 percent of the world's opium.
Based on reporting by Interfax and AP