The US Marine Corps has censured three officers for their roles in investigating the killing of Iraqi civilians in Haditha two years ago.
The major-general and two colonels were found to have "demonstrated lack of due diligence" but cleared of any cover-up.
The censures may affect promotions and retirement benefits.
The disciplinary action, which cannot be appealed, came as a preliminary hearing continued in the Haditha case for Staff Sergeant Frank Wuterich, 27, who is accused of unpremeditated murder in the slaying of 17 of the Iraqis.
The text of the letters of censure was not released.
The Marine Corps said Major-General Richard Huck, who commanded the 2nd Marine Division, was censured for the "actions he took and failed to take" in response to the killings.
Colonel Stephen Davis was censured for failure to take action when informed of the killings while Colonel Robert Sokoloski was cited for unsatisfactory performance of his duties.
Lieutenant-General James Mattis, who reviewed their performance, "did not find any evidence that these senior officers intended to cover up the incident," the marines said in a statement.
"He did determine that their actions, or inactions, demonstrated lack of due diligence on the part of senior commanders and staff."
Former commander of the II Marine Expeditionary Force, Major-General Stephen Johnson, was exonerated.
In November 2005, 24 Iraqi civilians in Haditha including women and children were killed by a marine squad following a bomb attack which killed one soldier.
General James Conway, the Marine Corps commandant, said the "actions, inactions and decisions" of the three officers after the incident "did not meet the high standards we expect of marine senior officer leadership".
Wuterich's case
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Wuterich is accused of unpremeditated
murder in the Haditha slayings [Reuters] |
The preliminary hearing in Wuterich's case is expected to conclude on Thursday before a final decision is made on whether he should be court-martialled, Lieutenant-Colonel Paul Ware, the investigating officer overseeing the Haditha case, said.
Four enlisted marines were charged with murder and four officers were charged with dereliction of duty for failing to investigate the deaths in the case.
Charges have so far been dropped against three of the men.