From the BBC website:

US inquiry into civilian killings


US troops fear fresh suicide attacks at checkpoints
American military officials have begun an investigation into the deaths of at least seven women and children at the hands of US troops at a checkpoint in central Iraq.
Two other Iraqis were wounded when the vehicle they were all travelling in was fired on after it reportedly failed to stop at the road block near the city of Najaf, south of Baghdad.



There are two different versions of what happened. According to coalition Central Command, the soldiers first fired warning shots, then aimed at the engine, and finally targeted the vehicle itself.


But the Washington Post quotes a senior officer as telling a subordinate: "You killed a family because you didn't fire a warning shot soon enough."