A top US Army commander in Iraq has ordered an investigation into allegations of yet another atrocity committed by US soldiers in Iraq. The case involves a particularly gruesome and sadistic episode, in which an Iraqi woman was allegedly stalked, raped and murdered. Three other members of her family were killed, and the corpse of the violated woman was burned.

The revelation of these killings follows a string of exposures in recent weeks of execution-style murders and other violent crimes against Iraqi civilians by US troops.

The latest investigation involves an incident that occurred on March 12 in the market town of Mahmoudiyah, about 20 miles south of Baghdad. The Associated Press reported that the incident involved five soldiers from a unit of the 502nd Infantry Regiment, which is attached to the Fourth Infantry Division.

Military officials told the Associated Press that the soldiers had noticed the woman on previous patrols and that the killings appeared to have been “a crime of opportunity.” For months, military officials attributed the civilian deaths to “insurgent activity.”

The suspects in these killings were from the same unit as the two US soldiers whose bodies were found mutilated earlier this month, after they had been taken captive at a military checkpoint. According to numerous news sources, soldiers in the unit came forward on June 23, following the discovery of the bodies of the two captured soldiers, and revealed that American troops had been responsible for the four civilian deaths in March.

According to a network news report that aired Friday evening, one or more soldiers spoke out about the incident at a meeting of soldiers in the unit called by officers to discuss the deaths of their two comrades.

The investigation into the March 12 killings was ordered on June 24 by Maj. Gen. James D. Thurman, commander of the Army’s 4th Infantry Division, to which the 502nd is attached. Although no charges have been filed in the case, and the investigation is “in the very early stages,” a preliminary inquiry “found sufficient information existed to recommend a criminal investigation into the incident.”

The Mahmoudiyah case is only the latest investigation into killings of Iraqi civilians by US soldiers that has been announced in recent weeks. The Pentagon is still investigating the deaths of civilians last November in the predominantly Sunni town of Haditha, in which US Marines apparently went on a rampage, executing 24 civilians, including women and children.

At least 11 civilians died in the village of Ishaqi, 60 miles north of Baghdad, on March 15. While eyewitness and video accounts back villagers’ claims that the civilians were deliberately killed by US troops, the US military moved quickly to exonerate US soldiers of any misconduct.

In early June, the Army charged four US soldiers with killing three detainees in May and then threatening to kill another soldier if he reported the shootings. Also in June, seven Marines and one Navy corpsman were charged with murder and kidnapping in the April killing of an Iraqi villager on the western outskirts of Baghdad. The charges state that after shooting the Iraqi four times in the face, his killers planted a rifle and shovel near the body to make it appear that the victim was an insurgent.

The regularity with which wanton killings of Iraqi civilians are being reported demonstrates that such atrocities are not mere anomalies. These cases provide only a glimpse of a pattern of homicidal violence that is undoubtedly widespread and, if anything, increasing in frequency and savagery.

They demonstrate that American forces in Iraq are being brutalized and dehumanized by their involvement in a filthy colonialist enterprise. The US occupation of Iraq—entailing the indiscriminate bombing of towns and villages, mass roundups of men, women and even children, incarceration and sadistic torture—exhibits in the most vicious forms the mass murder and repression that have been part and parcel of every imperialist effort to conquer and subjugate a foreign population.

The most recent revelations cast a sharper light on previous infamies, from the sexually perverse abuse of prisoners at Abu Ghraib to the leveling of large parts of Fallujah. They expose utterly the official lie that the photos of American soldiers lording it over naked, humiliated and helpless Iraqis at Abu Ghraib were mere aberrations—the actions of a few “bad apples.”

No. These images were snapshots of the conditioning of the American “volunteer Army” to carry out a criminal mission, one that requires the disintegration of all humane and democratic instincts, affecting not only the victims of US violence, but inflicting irreparable psychological, emotional and moral damage on those who carry it out.

Where does the real responsibility lie for this nightmare of death and destruction? As the saying goes, a fish rots from the head.

The climate for criminal actions carried out by troops on the ground has been created by Bush, Cheney, Rumsfeld and company. Their motto is: Anything goes. No lie is too great, no crime too horrific in the pursuit of the predatory interests of the ruling elite they serve, in the Middle East with its oil wealth, and throughout the world.

They above all must be held accountable and brought to justice for plotting and launching an illegal war of aggression.