8 Afghan Police Officers Killed In `Friendly Fire'

This headline from AP would suggest yet another error by American troops.
However, in the story itself is the explanation:

Mistaking each other for the enemy, Afghan police fired four dozen grenades and U.S.-led coalition troops fought back with helicopter gunships in a fierce battle that left eight Afghans dead before dawn Tuesday

This was how I heard hooks for the national newscasts as well. The inference being, we screwed up again. The troops defended themselves after being attached with 48 RPG's. This is unfortunate for the Afghan police.