3 - U.S. Soldiers killed Friday in the so called green-on-blue assault.
An Afghan police officer opened fire on four American soldiers he had invited for a meal Friday, killing three of them, Afghan officials said, in the third so-called green-on-blue assault in just four days. KABUL, Afghanistan
6 - Americans killed by their Afghan partners in a single day, officials said Saturday, 8-11-12
I placed 2 - links below to read the more about the killings and violence still an ongoing problem.
The Taliban claimed responsibility for both attacks on Friday in Helmand province an area of the south where insurgents have wielded their greatest influence. "The enemy who does not want to see Afghanistan have a strong security force, targets military trainers," Karzai said in a statement.
Such assaults are on the rise and have heightened mistrust between foreign forces. 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.