A U.S. soldier was killed after stepping on a land mine while on a patrol in southern Afghanistan, the military said Saturday, bringing to 200 the number of American troops killed here since the Taliban was ousted in 2001.

The soldier was part of an offensive patrol in a part of Helmand province that has been racked by rebel violence recently, a military statement said.

A U.S. military spokeswoman, Sgt. Marina Evans, said it was not known immediately whether the mine had been laid recently, targeting the patrol, or whether it was one of thousands left over from a quarter-century of war.

"It's a sad day any time a comrade dies in this ongoing struggle," Brig. Gen. Jack Sterling, a deputy commander of the U.S.-led coalition, said in the statement.

The soldier's name was withheld until his family could be notified.

The death brought to 200 the number of U.S. service members who have died in and around Afghanistan since 2001, according to military figures. This year has been the deadliest yet for the nearly 30,000-member U.S.-led coalition force.

Fighting escalated sharply ahead of Sept. 18 parliamentary elections, with more than 1,300 people killed, including hundreds of Taliban-led fighters during the past seven months. Afghans voted under relatively peaceful circumstances despite Taliban threats of violence.