Afghan security forces have seized more than 15 tons of illegal drugs in a series of operations across the country.

The nation's top drug enforcement official, Lieutenant General Mohammed Daoud Daoud said Saturday the seizures over the past 10 days included one ton of heroin. He also is quoted by the French news agency as saying that more than a dozen men were arrested.

Daoud said the government is seeking to increase efforts to block cultivation of poppy and other drugs.

The United Nations has reported that opium production is up 60 percent this year in Afghanistan. The world body says much of the proceeds of the illegal drug trade are funding insurgent activities and fueling political corruption.