A least nine people have been killed and 16 wounded in a coordinated attack by 11 suicide bombers in the eastern Afghan city of Khost.

Afghan army personnel and police, working with international forces, took nearly six hours to subdue the attackers, with heavy gunfire reported before all bombers had detonated their explosives.

The militants targeted the provincial governor's compound and the municipality, according to police.

Other Afghan officials said many of the dead were security officers.

The Taliban claimed responsibility for the attacks.

Earlier, a suspected US drone attack killed up to eight militants in a remote Pakistan tribal area near the Afghan border this morning.

The attack occurred in the village of Sara Khwara in South Waziristan, and was the second such strike in the semi-autonomous tribal zone in three days.

US military head sacked

Late yesterday, the top US commander in Afghanistan was sacked to make way for 'new thinking' at a pivotal moment in the seven-year-old war.

General David McKiernan is being replaced after less than a year on the job.

US Defense Secretary Robert Gates said: 'Our mission there requires new thinking and new approaches from our military leaders.'

Lt Gen Stanley McChrystal, a former commander of special operations forces in Iraq and Afghanistan, will replace Gen McKiernan.

Mr Gates said that the US has a new strategy, a new mission and a new ambassador, and added: 'I believe that new military leadership also is needed'.

The change comes as President Barack Obama escalates the war against a spreading Taliban insurgency, approving deployments that will double the size of the US force in Afghanistan to 68,000 by the autumn.

The new commander will face growing instability in neighbouring Pakistan and a public outcry among Afghans over rising civilian casualties from US air strikes.