(KABUL, Afghanistan) -- Three U.S. troops were among 21 people who died Wednesday when a suicide bomber detonated explosives at a military checkpoint in the southeastern Afghan city of Khost.
The American fatalities boost this year's death toll of U.S. service personnel to 149. Estimates vary on the total number of U.S. troops who have died in the war since 2001, although one figure puts the number at 2,013.
Witnesses said that a man who blew himself up got close enough to the checkpoint to inflict massive casualties. Among those killed were an Afghan interpreter embedded with the Americans forces as well as 17 Afghan civilians who were nearby. Thirty-two people were also wounded in the blast.
While overall attacks by the Taliban and their allies are down this year, the militants have recently stepped up their assaults in an effort to undermine the gradual transfer of security responsibilities from U.S. and NATO forces to Afghan soldiers and police.
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