KABUL, Afghanistan -- A man wearing an Afghan army uniform killed three U.S. soldiers, the U.S. military command said. Afghan officials said the victims were special forces troops.
"All we know is that they were killed by an Afghan in a uniform of some sort," a spokeswoman for NATO-led forces in Afghanistan told Reuters, adding that it was too early to say if the shootings were by a rogue security force member or a Taliban infiltrator.
The attack is the third killing this week of coalition soldiers by Afghans who are training to take over responsibility for security once most international forces leave in 2014.
Afghan officials said the three men were all special forces members and were killed while attending a meeting in the Sangin District of Helmand province late on Thursday.
So-called "green on blue" shootings, in which Afghan police or soldiers turn their guns on their Western mentors, have seriously eroded trust between the allies.
According to NATO, there have been 24 such attacks on foreign troops since January in which 28 people have been killed. Last year, there were 21 attacks in which 35 people were killed.
In a grim 24 hours for the NATO-led force, three U.S. soldiers and an American aid worker were killed earlier on Thursday in the eastern province of Kunar in an attack by a suicide bomber.
The Associated Press and Reuters contributed to this report.
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