The dead all lost their lives in the first blast, which was a car bomb that ripped through a residential area of the town of Tirin Kot, the deputy governor of Uruzgan province governor Mohammad Nabi told AFP.

The US-led coalition said meanwhile it had killed more than two dozen Taliban in a series of battles across Afghanistan in the past 24 hours. A teenage boy was killed in the crossfire.

"Nine Afghan nationals including adults and children have been martyred," provincial police chief General Mohammad Qasim said. Five were children, aged around 12, and the rest were young men, he said.

"Seven other Afghans have been wounded including one woman," he said.

Nato's International Security Assistance Force said one of its soldiers was killed and three wounded.

The 37-country Isaf gave no details of the attack and does not release the nationalities of its casualties, leaving this to the home nations of its soldiers.

Most of the Isaf soldiers in Uruzgan are Australian and Dutch nationals.

Another suicide bomber struck hours later in the city of Kandahar, about 100km away, police said.

"Five civilians were wounded in a suicide attack on a Nato convoy," Kandahar province police chief Ismatullah Alizay told AFP. Isaf said it suffered no casualties.

Southern Afghanistan has been hard hit by a fierce Taliban-led insurgency. Attacks are mainly targeted at Afghan and foreign forces but kill and maim more civilians.