Pakistan, our "ally from hell," doesn't seem to be helpful toward American forces deployed on its border with Afghanistan: The Washington Post's Joshua Partlow reports that U.S. soldiers aren't sure if a recent firefight was with insurgents or Pakistani forces. The incident occurred on October 25:

The soldiers with the 3rd platoon launched a warning flare, called a "red star cluster," to identify themselves. For a moment, according to a U.S. military summary of the incident, the firing stopped; then it resumed. The U.S. soldiers shot back with their rifles and handheld 60mm mortars — a rare direct-fire engagement with a Pakistani border post.

But as with much concerning Pakistan’s role in the Afghan war, this firefight has left American soldiers at a loss for a clear explanation. It could have been a case of Pakistani soldiers firing on U.S. troops to provide cover for insurgents maneuvering nearby, as some U.S. soldiers initially concluded. Or, insurgents could have been firing from a checkpoint that had already been abandoned by Pakistani troops.

Niether explanation would appear to give the U.S. much faith in the Pakistani military. As for how the incident was resolved on October 25th, it happened like this:

The firefight on Oct. 25 remains something of a mystery. After the first few minutes of firing from the Pakistani Frontier Corps checkpoint, U.S. aircraft spotted a group of insurgents about 200 yards to the west firing rocket-propelled grenades at the American soldiers. U.S. military aircraft dropped two 500-pound bombs and killed the insurgents.