Afghan President Hamid Karzai's younger brother – a powerful figure in the country's south – has been assassinated at his home, apparently by a trusted bodyguard.

An unnamed Afghan intelligence official says Ahmad Wali Karzai was shot and killed Tuesday by a senior member of his security detail in Kandahar city. The gunman, who was identified by the official as Sardar Mohammad, was then killed by Wali Karzai's bodyguards.

The Taliban claimed responsibility for the assassination.

In Kabul, Afghan President Hamid Karzai told reporters the killing of his younger brother represents the suffering of all Afghan people.

Ahmad Wali Karzai, the head of the provincial council in southern Kandahar province, was a controversial figure. While he was seen as a key powerbroker in the region and an ally to international forces fighting the Taliban, Wali Karzai had also been accused of corruption and drug trafficking – allegations he had denied.

The commander of U.S. and NATO forces in Afghanistan, David Petraeus, said Tuesday he condemns the murder of Wali Karzai and that NATO forces will support the Afghan government's efforts to bring justice to those responsible.

Wali Karzai survived at least two previous attempts on his life in recent years. In May 2009 insurgents attacked his motorcade, killing one of his bodyguards. Wali Karzai also escaped an earlier attack on his provincial council facilities in Kandahar.

Also Tuesday, Italian defense officials say a roadside bomb killed an Italian soldier in the western Afghan province of Farah.