KANDAHAR, Afghanistan (AFP) - An Afghan district police chief was killed in an ambush by militants in the volatile southern province of Helmand on Wednesday, officials said.

Tooryalai Khan, police chief of Helmand's Marjah district, was leading an operation against Taliban insurgents in the area when he was ambushed early in the morning, said provincial spokesman Omar Zewak.

His bodyguard was wounded in the attack.

Ismael Hotak, a senior provincial police officer, confirmed the incident and said Khan was appointed in the district six months ago.

No one has claimed responsibility for the attack. But the Taliban, who are waging an insurgency against the US-backed Afghan government, have a strong presence in southern provinces.

Helmand is one of the most volatile provinces, and the heart of the opium trade. About half of the poppies grown in the country are planted in Helmand.