The father of a U.S. Marine killed by a roadside bomb in western Iraq in November believes his son's comrades did nothing wrong despite a criminal investigation into events that left more than 20 Iraqi civilians dead, including women and children.

"It's very hard for me, I don't even listen to the news," Martin Terrazas said of reports of the mass killings in Haditha, in Iraq's Anbar province. "The insurgents were hiding in there with the kids."

Lance Cpl. Miguel Terrazas was killed when his military convoy hit a roadside bomb in the western Iraqi city of Haditha. Initial accounts from Marines indicated that a fight with insurgents ensued and that 15 civilians and eight insurgents were killed in the explosion and subsequent firefight.

But now, separate investigations seek to determine whether the Nov. 19 killings were criminal and whether the Marines involved and their commanding officers tried to hide the truth. The Pentagon has said little publicly.

The New York Times reported Wednesday that evidence uncovered in February and March contradicts the claims made by Marines about how the Iraqis died.

Citing an unnamed senior U.S. official, the Times reported that a review of the incident by Col. Gregory Watt in Baghdad has uncovered evidence that casts doubt on initial reports by Marines involved.

"There were enough inconsistencies that things didn't add up," the unnamed official said, according to the Times. The report cites death certificates that show all the Iraqi victims had been shot, many in the head and chest.

Luis Terrazas, the uncle of the Marine killed in the November attack and a former Marine himself, said Marines are trained not to lose their cool under pressure.

"Jarheads don't just go out and kill because they get frustrated," said Luis Terrazas, 39. "Their training is exquisite. It just doesn't make sense."

Martin Terrazas, who said he has met with many Marines from his son's unit, said the men didn't give him many details of the attack.

"They wouldn't go into details," Martin Terrazas said. "I just needed to know if my son suffered. They just said it wasn't a pretty sight."

The Marines also told the grieving father that they did what was necessary to survive.

Miguel Terrazas was in the midst of his second tour of duty in Iraq when he was killed. His family says he knew how dangerous his duty was, having survived an ambush during his first tour.

"Hearing my son's comrades is very hard," Martin Terrazas said. "Those Marines just did their job. Some of these kids were saying, 'We have to live with it.'"

The parents of two Marines from the 3rd Battalion, 1st Marine Regiment, 1st Marine Division, 1st Marine Expeditionary Force based at Camp Pendleton in Calif. told The Associated Press that their sons were ordered to take pictures of the scene and help remove the bodies. The parents of Lance Cpl. Roel Ryan Briones, 21, and Lance Cpl. Andrew Wright, 20, said memories of the killings have haunted the Marines.

Briones' mother said her son did not witness the killings. Wright's parents declined to say what their son saw that day.