A Taliban attack on a police post in southern Afghanistan has killed nine police officers.

The early morning ambush took place in the Nahri Sarraj district of Helmand province.

The interior ministry said an operation had been launched in the area to hunt down the attackers.

Meanwhile, a suspected US missile strike killed at least four militants in a tribal region of Pakistan near the border with Afghanistan.

The attack took place in the Essokhel area, around 30km east of Mir Ali town in the North Waziristan tribal region.

Confirming the strike, another official said the nationality of those killed in the strike was not immediately known.

The strike is the second in as many days by the drones, with a missile yesterday killing up to seven alleged al-Qaeda militants in the nearby Makeen area of South Waziristan.