Guys from the same unit. The soldier that led the whole thing (PFC Green) had already been sent home for saying crazy shyt and being racist. He was medically discharged because no one really knew he did it. The locals knew it was an American because the three guys involved left behind shotgun shells from the breach gun they used.
He and the other two eventually got caught when the guy, they left behind to watch their little observation post, put two and two together and told on them. Even after he told no one believed him besides the chaplain and no one wanted the trouble. He told his dad he was being ostracized and punished for telling. His dad got in contact with a senator and the media. There was a big deal about whether to let the Iraqi’s try and imprison the three but they stayed stateside and were locked up forever. Green finally bushed himself in Federal prison.
The battalion was stretched so thin that they did patrols with 6 people at most. They held check points all day with one vehicle. The 4 were at a checkpoint and were surrounded, outnumbered. Nobody could get there fast enough because of the distance. There was a fight but 2 were killed on the spot the other 2 were captured and tortured mercilessly to death. None of them had anything to do with it.
The same thing happened a year later to some 10th mtn dudes who went to sleep during a convoy in the same area.
EDIT: I was wrong about the 4. It was originally 3 at the checkpoint. Also I mentioned earlier that they were 2/502nd but it was 1st battalion.