Chief of General Staff Lt.-Gen. Dan Halutz expressed regret Saturday for the killing of eight Palestinian civilians in Gaza, but stopped short of taking responsibility for the incident, saying an investigation was ongoing. The investigation has so far ruled out the fire resulted from a gunship or an airstrike, but the possibility remains that artillery rounds were fired, Halutz told reporters. There is also the possibility that the incident was caused by Palestinian militants, who accidentally misfired one of their rockets, he said. "First I want to express our, my, regret over the incident where uninvolved civilians where harmed, but I stress that the expression of regret does not mean we are taking responsibility for the incident," Halutz said. "The ... investigation has not yet been completed."