Afghan officials said at least five people were killed on March 24 when a roadside bomb went off in the southern province of Uruzgan.
Gulab Khan, the security chief of the province, said the blast killed a former Afghan senator, a tribal elder, and two bodyguards.
The Uruzgan governor's office said the former senator, Khairo Jan, was working in Uruzgan to unify local residents to help bring peace to Afghanistan.
No one has so far claimed responsibility for the attack.
Southern Afghanistan has been the center of a 10-year Taliban insurgency since the U.S.-led invasion in 2001.
Meanwhile, The Italian military has said one Italian soldier was killed on March 24 and five injured in a mortar attack on a base in western Afghanistan.
Italian soliders came under mortar fire at a base in Gulistan in an area under Italian control in Herat Province.
Italy has 3,800 soldiers in Afghanistan as part of NATO's International Security Assistance Force but plans to reduce its deployment starting this year.
Some 50 Italian soldiers have died in Afghanistan since the U.S.-led invasion in 2001.