KABUL, Afghanistan - An Afghan working on an installation shared by Afghan and foreign forces shot to death three U.S. service members, raising to six the number of Americans killed by their Afghan partners in a single day, officials said Saturday.
The newly announced killings took place Friday, the same day that an Afghan policeman gunned down three U.S. Marines in a separate attack in southern Afghanistan.
Such assaults are on the rise and have heightened mistrust between foreign forces and the Afghan soldiers, police and others they are training and mentoring.
Four of the attacks occurred in the past week, raising questions about the safety of international trainers more than 10 years into the war. The U.S.-led coalition insists the attacks do not represent the overall security situation in Afghanistan and that they have not impeded ongoing work to hand over security to Afghan forces by the end of 2014.
Most of the attacks have been carried out by Afghan police and soldiers or militants wearing their uniforms. There have been 26 such attacks so far this year, resulting in 34 deaths, according to the U.S.-led coalition.
The Taliban claimed responsibility for both attacks on Friday in Helmand province - an area of the south where insurgents have wielded their greatest influence.
In the first attack, an Afghan police officer shot and killed three Marines after sharing a pre-dawn meal with them in the volatile Sangin district, according to Afghan officials. A U.S. Defense Department official confirmed that the dead Americans were Marine Special Operations Forces.
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, a village-level defense force overseen by the Ministry of Interior. 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.
Sidiq Sidiqi, a spokesman for the Afghan Ministry of Interior, told reporters on Saturday that the shooter may have been a member of the Afghan Local Police, rather than the National Police. He said investigators were still reviewing the case.
Then at around 9 p.m. Friday in the Garmser district farther south, an Afghan working on an installation shared by coalition and Afghan forces shot and killed three other international troops, said Maj. Lori Hodge, a spokesman for the coalition in Kabul. A U.S. defense official confirmed the three victims also were Americans.
Hodge said both shooters had been detained.
Sidiqi said initial reports indicated that the gunman in the Garmser attack was a student not associated with the Afghan police forces.
But Taliban spokesman Qari Yousef Ahmadi told The Associated Press that a member of the Afghan security forces in Garmser killed the international soldiers.
Helmand has been particularly deadly for these so-called "green-on-blue" attacks. Since 2009, 18 international soldiers, including 14 from Britain, have been killed in such attacks in Helmand. The most recent was on July 1 when three British service members were killed in Sangin by a gunman wearing an Afghan National Civil Order Police uniform.
Afghan President Hamid Karzai condemned the latest killings, ordered investigations into the incidents and directed relevant Afghan authorities to work to ensure the safety within training and security institutions.
"The enemy who does not want to see Afghanistan have a strong security force, targets military trainers," Karzai said in a statement.