Police say Taliban militants have attacked and killed seven officers cutting down a field of opium poppies in southern Afghanistan.

Provincial police chief Sayad Agha Saqib says five Taliban militants were also killed in the clash Monday morning in the Maiwand district of Kandahar province. The insurgents attacked the police with rifles and rocket-propelled grenades.

The Afghan government eradicated almost 16,000 hectares (40,000 acres) of poppies last year, but the country's farmers still grew 193,000 hectares (477,000 acres) of poppies, a record haul.

Afghanistan last year produced 93 percent of the world's opium, the main ingredient in heroin.