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(CBS/AP) KABUL, Afghanistan – An Afghan police officer shot and killed three U.S. Marines after sharing a meal with them before dawn Friday and then fled into the desolate darkness of southern Afghanistan, the third attack on coalition forces by their Afghan counterparts in a week.

Thirty-one coalition service members have now died this year at the hands of Afghan forces or insurgents disguised in Afghan uniforms, according to NATO — a dramatic rise from previous years.

U.S. officials told CBS News correspondent David Martin that the three slain troops were members of a Marine special operations force. Afghan sources in Helmand told CBS News Kabul bureau chief Fazul Rahim that they were part of a team overseeing the training and recruitment of Afghan local police. The sources said it was one of the police officers who opened fire on his mentors during dinner.

Friday’s deadly shooting took place in the volatile Sangin district of Helmand province, said U.S. military spokeswoman Maj. Lori Hodge. Sangin was a Taliban stronghold for years and 마카오 환전 has one of the highest concentrations of improvised explosive devices, or IEDs, in the country.

Sangin’s district chief and the Taliban both identified the gunman as Asadullah, a member of the Afghan National Police who was helping the Marines train the Afghan Local Police.

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Taliban spokesman Qari Yousef Ahmadi said by telephone that the attacker joined the insurgency after the shooting.

“Now, he is with us,” Ahmadi said.

The district chief, Mohammad Sharif, said the shooting happened at a police checkpoint after a joint meal and a security meeting. The meal took place before dawn because of Ramadan, the month in which Muslims abstain from food during daylight hours.

The shooting brings the number of fatal “green-on-blue” incidents – in which Afghan security forces turn on their Western allies – to 25 over the last 12 months, including those which didn’t result in coalition fatalities.The attack brings to eight the number of Americans killed in Afghanistan this week, including one civilian working for the State Department.

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