"Three U.S. Forces-Afghanistan service members died following an attack by an individual wearing an Afghan uniform in southwest Afghanistan today," according to a statement from the International Security Assistance Force - Afghanistan.
NPR's Soraya Sarhaddi Nelson, who is in Kabul, says more than one individual in an Afghan military or police uniform may have done the shooting. She's reports that "a senior Afghan police official" said the Americans were invited to a dinner and that during the meal several police recruits stood up and opened fire.
The New York Times writes that "Muhammad Sharif, the governor of Sangin District of Helmand Province, where the killings took place," said it was a local police commander who invited the Americans "to eat dinner at his check post on Thursday."
There's been a claim of responsibility from someone saying he speaks for the Taliban.
CNN notes that today's attack "came a day after Secretary of State Hillary Clinton condemned an attack in the eastern Kunar province that killed USAID Foreign Service Officer Ragaei Abdelfattah, three ISAF service members and an Afghan civilian, and injured a State Department Foreign Service officer. That led Clinton to issue a statement "strongly" condemning the attack — but adding that "it strengthens our resolve to continue working with the Afghan people to build their economy, democratic institutions, rule of law, and security so that Afghanistan can stand on its own as a stable, secure, and increasingly prosperous country."
The Times adds that:
"The problem of Afghan forces killing their coalition counterparts has intensified in recent years in Afghanistan, where's the military's nomenclature for such violence — it calls them 'green-on-blue' killings — has entered widespread usage."
According to Soraya, the latest attack brings to 28 the number of U.S. military personnel killed this year by Afghan police officers, soldiers or militants who had disguised themselves in Afghan uniforms. The Times puts the number higher, writing that "the latest episode, if confirmed, would bring the total number of coalition service members intentionally killed this year by Afghan forces to 34 in 25 attacks. In 2011, a total of 35 were killed in 21 attacks."