Washington ? The Marine Corps’ top general left for Iraq on Thursday to remind Marines that it’s important to maintain their core values of “honor, courage and commitment” even in the middle of a bitter counterinsurgency where the differences between right and wrong, friend and foe, are often blurred.

Marine Commandant Gen. Michael Hagee’s departure came a day after Marines in Iraq announced a criminal investigation into allegations that Marines killed an Iraqi civilian April 26 near the town of Hamandiyah, west of Baghdad. Investigators also are probing a Nov. 19 incident in which a group of Marines allegedly shot and killed 23 Iraqi civilians in the town of Haditha, according to survivors interviewed by Knight Ridder.