A roadside bomb explosion in southern Afghanistan on Thursday killed two U.S. soldiers and wounded two, the U.S. military said.

The soldiers were traveling in an armored vehicle north of Kandahar (search), part of a convoy supporting a road construction project, the U.S. military said in a statement.

The two wounded soldiers were evacuated to Kandahar Airfield (search) for medical treatment. Both were in stable condition, the statement said.

"These terrorists are attacking the very forces working to improve Afghanistan," said Brig. Gen. Jack Sterling (search), a deputy commander of the U.S.-led coalition. "It's unconscionable that the Taliban would do something like this. They only offer death and continued suffering to the people of Afghanistan."

He said the road project was linking the southern main city of Kandahar with Tirin Kot, a district about 60 miles to the north.

The deaths bring to 182 the number of U.S. service members killed in and around Afghanistan since the start of Operation Enduring Freedom (search) in 2001.

There has been an increase in U.S. military casualties in recent months as Taliban-led militants have stepped up attacks across the country. Most of the violence has been across southern and eastern parts of the country, leaving about 1,000 people dead.