A series of co-ordinated suicide attacks against a small town in northern Iraq by al-Qaeda has caused the highest death toll of any single attack since the conflict began.
Early report say that more than 200 people were killed when five explosive laden trucks were detonated in the town of Kahtaniya on Tuesday evening.
But this was no ordinary truck bombing for the victims were mainly Yazidis, members of an obscure pre-Christian religion.
If anyone in the Iraq conflict has been neutral it is the Yazidis.
The sect's members have neither supported Saddam Hussein, the US or the insurgency.
But to their al-Qaeda attackers all that matters is that they are not Muslim and, worse, that they are not members of the Ahl al-Kitab, the 'People of the Book' (such as Jews and Christians) who Muhammad said should be tolerated by Muslims.
These attacks show that al-Qaeda is not a movement which attacks only in self-defence or to right past wrongs.
Instead al-Qaeda's followers believe that people should be killed not for what they have done but because of what they believe.