Up to eighteen people are believed to have been killed in two separate explosions in Afghanistan.

Eight children and a police officer were among the dead in a suicide bomb attack in the eastern city of Khost.

It's understood the bomber wanted to target a joint patrol of Afghan and international forces, but was grabbed by a policeman and then detonated himself.

While nine people were killed and 13 others injured after a suicide bomber blew himself up at an entrance to the Afghan Defence Ministry in central Kabul.

The Taliban have claimed responsibility for the attack in the Afghan capital which came hours after new US Defence Secretary Chuck Hagel arrived in the country to hold talks with President Hamid Karzai and NATO officials.