Even if this does sound a lot like My Lai:

Here’s what all participants agree on: at around 7:15 a.m. on Nov. 19, a U.S. humvee was struck by a powerful improvised explosive device (ied) attached to a large propane canister, triggered by remote control. The bomb killed Terrazas, who was driving, and injured two other Marines. For U.S. troops, Haditha, set among date-palm groves along the Euphrates River, was inhospitable territory; every day the Marines found scores of bombs buried in the dirt roads near their base. Eman Waleed, 9, lived in a house 150 yards from the site of the blast, which was strong enough to shatter all the windows in her home. “We heard a big noise that woke us all up,” she recalls two months later. “Then we did what we always do when there’s an explosion: my father goes into his room with the Koran and prays that the family will be spared any harm.” Eman says the rest of the family—her mother, grandfather, grandmother, two brothers, two aunts and two uncles—gathered in the living room. According to military officials familiar with the investigation, the Marines say they came under fire from the direction of the Waleed house immediately after being hit by the ied. A group of Marines headed toward the house. Eman says she “heard a lot of shooting, so none of us went outside. Besides, it was very early, and we were all wearing our nightclothes.” When the Marines entered the house, they were shouting in English. “First, they went into my father’s room, where he was reading the Koran,” she claims, “and we heard shots.” According to Eman, the Marines then entered the living room. “I couldn’t see their faces very well—only their guns sticking into the doorway. I watched them shoot my grandfather, first in the chest and then in the head. Then they killed my granny.” She claims the troops started firing toward the corner of the room where she and her younger brother Abdul Rahman, 8, were hiding; the other adults shielded the children from the bullets but died in the process. Eman says her leg was hit by a piece of metal and Abdul Rahman was shot near his shoulder. “We were lying there, bleeding, and it hurt so much. Afterward, some Iraqi soldiers came. They carried us in their arms. I was crying, shouting ‘Why did you do this to our family?’ And one Iraqi soldier tells me, ‘We didn’t do it. The Americans did.’” Time was unable to speak with the only other survivor of the raid, Eman’s younger brother, who relatives say is traumatized by the experience. U.S. military officials familiar with the investigation say that after entering the house, the Marines walked into a corridor with closed doors on either side. They thought they heard the clack-clack sound of an AK-47 being racked and readied for fire. (Eman and relatives who were not in the house insist that no guns were there.) Believing they were about to be ambushed, the Marines broke down the two doors simultaneously and fired their weapons. The officials say the military has confirmed that seven people were killed inside the house–including two women and a child. The Marines also reported seeing a man and a woman run out of the house; they gave chase and shot and killed the man. Relatives say the woman, Hiba Abdullah, escaped with her baby.

According to military officials, the Marines say they then started taking fire from the direction of a second house, prompting them to break down the door of that house and throw in a grenade, blowing up a propane tank in the kitchen. The Marines then began firing, killing eight residents—including the owner, his wife, the owner’s sister, a 2-year-old son and three young daughters.

The Marines raided a third house, which belongs to a man named Ahmed Ayed. One of Ahmed’s five sons, Yousif, who lived in a house next door, told Time that after hearing a prolonged burst of gunfire from his father’s house, he rushed over. Iraqi soldiers keeping watch in the garden prevented him from going in. “They told me, ‘There’s nothing you can do. Don’t come closer, or the Americans will kill you too.’ The Americans didn’t let anybody into the house until 6:30 the next morning.” Ayed says that by then the bodies were gone; all the dead had been zipped into U.S. body bags and taken by Marines to a local hospital morgue. “But we could tell from the blood tracks across the floor what happened,” Ayed claims. “The Americans gathered my four brothers and took them inside my father’s bedroom, to a closet. They killed them inside the closet.”

The military has a different account of what transpired. According to officials familiar with the investigation, the Marines broke into the third house and found a group of 10 to 15 women and children. The troops say they left one Marine to guard that house and pushed on to the house next door, where they found four men, one of whom was wielding an AK-47. A second seemed to be reaching into a wardrobe for another weapon, the officials say. The Marines shot both men dead; the military’s initial report does not specify how the other two men died. The Marines deny that any of the men were killed in the closet, which they say is too small to fit one adult male, much less four. According to the military officials, the series of raids took five hours and left at least 23 people dead. In all, two AK-47s were discovered. The military has classified the 15 victims in the first two houses as noncombatants. It considers the four men killed in the fourth house, as well as four youths killed by the Marines near the site of the roadside bombing, as enemy fighters. The question facing naval detectives is whether the Marines’ killing of 15 noncombatants was an act of legitimate self-defense or negligent homicide. Military sources say that if the ncis finds evidence of wrongdoing, U.S. commanders in Iraq will decide whether to pursue legal action against the Marines.

The available evidence does not provide conclusive proof that the Marines deliberately killed innocents in Haditha. But the accounts of human-rights groups that investigated the incident and survivors and local officials who spoke to Time do raise questions about whether the extent of force used by the Marines was justified—and whether the Marines were initially candid about what took place. Dr. Wahid, director of the local hospital in Haditha, who asked that his family name be withheld because, he says, he fears reprisals by U.S. troops, says the Marines brought 24 bodies to his hospital around midnight on Nov. 19. Wahid says the Marines claimed the victims had been killed by shrapnel from the roadside bomb. “But it was obvious to us that there were no organs slashed by shrapnel,” Wahid says. “The bullet wounds were very apparent. Most of the victims were shot in the chest and the head–from close range.”

A day after the incident, a Haditha journalism student videotaped the scene at the local morgue and at the homes where the killings had occurred. The video was obtained by the Hammurabi Human Rights Group, which cooperates with the internationally respected Human Rights Watch, and has been shared with Time. The tape makes for grisly viewing. It shows that many of the victims, especially the women and children, were still in their nightclothes when they died. The scenes from inside the houses show that the walls and ceilings are pockmarked with shrapnel and bullet holes as well as the telltale spray of blood. But the video does not reveal the presence of any bullet holes on the outside of the houses, which may cast doubt on the Marines’ contention that after the ied exploded, the Marines and the insurgents engaged in a fierce gunfight.

UPDATE: The Pentagon has launched a criminal investigation.