Two U.S. soldiers and their Afghan interpreter were killed Saturday when their vehicle struck an improvised explosive device in southern Afghanistan, a statement issued by the U.S.-led military said.

A third soldier was wounded in the blast in Ghazni province, south of Kabul, the capital, according to the statement. The wounded soldier was flown to Kandahar airfield hospital and was in stable condition.

About 20,000 U.S.-led troops are stationed in Afghanistan hunting for Taliban and al Qaeda fighters, including Osama bin Laden.

Officials also said two people died Friday in an attack on a convoy of election workers. At least 30 gunmen shot at vehicles from the joint Afghan-U.N. electoral body as they passed through Char Cheno, a district of central Uruzgan province, Gov. Jan Mohammed Khan told the Associated Press. A dozen people have been slain preparing for the Oct. 9 elections.

Khan said two members of the voter registration team were killed and all four vehicles were destroyed after being strafed with assault-rifle and machine-gun fire.

The United Nations identified the victims as Mohammed Hashim, a training officer, and driver Mohammed Hussein. A third worker was missing.

The United Nations condemned "the murderous attack," spokesman Manoel de Almeida e Silva said.