Kabul  - Afghan and NATO-led troops killed 11 suspected Taliban and detained 20 others in separate clashes and airstrikes in southern Afghanistan, the alliance said Tuesday.

Ten insurgents were killed in combat with the International Security Assistance Force (ISAF) in Wardak province south-west of the capital, the alliance said in a statement.

The militants fired rockets at an ISAF base in Sayed Abad, on Kabul-Kandahar highway near Kabul city, the statement said, adding that NATO forces responded with artillery and close air support.

"After positive identification of the insurgents, aircraft engaged the insurgents with gunfire," the statement said.

Afghan and ISAF forces also killed one militant and detained 20 others in the adjoining province of Ghazni, a separate statement said.

The clash occurred in Spin Kholah village in Qarabagh district of the province after the combined forces engaged armed insurgents in the area, the statement said. It did not say if there were casualties among Afghan or international soldiers during the combat operations.

Afghan security analysts fear that the militants are surrounding Kabul city, which is a hub for thousands of Afghan and international forces, by penetrating provinces adjacent to the city.

The Taliban militants, who lost power in late 2001 in a US-led military invasion, are now operating in Wardak and Ghazni provinces in the south-western areas of the capital, and Logar in the south and Kapisa to the north-east.

Kabul's central localities have come under Taliban rocket attacks at least twice in the last three weeks that caused no casualties, but sparked widespread fear among the city's residents that the rebels were on the march towards the country's most important town.

Following their ouster, Taliban militants turned southern and eastern regions of the country bordering Pakistan into strongholds against Afghan and international forces. (dpa)