One U.S. soldier killed in Afghanistan mine blast

KABUL, Afghanistan -- Four Afghan aid workers were killed in an ambush Saturday, the latest victims in a bloody Taliban-led insurgency threatening plans for midyear elections. A U.S. soldier died in a mine blast, but the military said it was unclear if it was an attack.

The anti-tank mine exploded under a Humvee in eastern Afghanistan on Friday, killing the soldier and wounding nine others.

Investigators were examining whether the blast, northwest of the city of Ghazni, was a targeted attack on the patrol "or just a leftover mine," Lt. Col. Bryan Hilferty said. Afghanistan is littered with old munitions from more than two decades of war.

On Saturday, four Afghans working for a de-mining agency were fatally shot in an ambush in the west of the country, officials said.

The victims had just delivered supplies to de-miners working near Bala Buluk, about 340 miles west of the capital, Kabul, Patrick Fruchet of the U.N. de-mining program told The Associated Press.

"We had a team nearby who heard the shots being fired," Fruchet said. "When they got there, they were all dead."

An Afghan intelligence official said bullets found in their two shot-up vehicles were from AK-47 assault rifles and heavy machine guns.

Civilians have borne the brunt of a spate of recent attacks by suspected Taliban insurgents and their allies. The violence has left more than 100 dead in this year's first six weeks, mainly in the country's south and east.

Militants view Afghans working for aid groups or local authorities as fair targets in their campaign to unseat President Hamid Karzai and force foreign troops out of the country.

The United Nations has warned that elections planned for June could be derailed by the continuing violence, and by sluggish efforts to tame powerful warlords who could influence the vote.

Of the nine American soldiers injured Friday, two were being taken to a U.S. military hospital in Germany. Both were in stable condition, Hilferty said.

All the soldiers were from the 10th Mountain Division. Their names weren't released.

The blast near Ghazni, 80 miles south of Kabul, followed a Jan. 30 explosion at an arms depot near the same city. Eight U.S. soldiers died in what the military said appeared to have been an accident, in the deadliest day for U.S. troops in Afghanistan since 2001.

Peacekeepers in Kabul have also been targeted, losing two soldiers in suicide attacks last month.