FBI investigators have found that Blackwater security personnel shot and killed at least 14 of 17 civilians without justification on September 16 in Baghdad’s Nisoor Square, according to officials quoted in The New York Times.

The FBI report, which will soon be released, concludes that the Blackwater guards used recklessly lethal force. The Justice Department is now reviewing the findings.

Federal investigators found that only three of the 17 people killed could have been perceived as a threat at the time Blackwater guards opened fire. A medical student and his mother, a physician, travelling in a white sedan tried to enter Nisoor Square after it had been cleared of traffic; this might have been identified as a threat. One other civilian standing nearby might also have been seen as a legitimate threat.

However, no evidence was found to support Blackwater’s claim that their vehicles had been fired upon, causing contractors to return fire.

Investigators were especially critical of Blackwater’s opening fire on several civilians who were trying to flee the chaos, yet they stopped short of supporting the Iraqi government’s conclusion that the incident constituted a massacre.

“I wouldn’t call it a massacre, but to say it was unwarranted is an understatement,” said one official.

Federal prosecutors have not yet decided whether to seek indictments. It is unclear which laws might apply to the contractors, who are immune from prosecution in Iraq and under US criminal law.

It is believed that the case will be one of the first to be considered by new US Attorney General Michael Mukasey.

Congressman David Price (D-N.C.) recently sponsored a bill to make government contractors like Blackwater accountable under US law; the bill was passed 389-30 in the House last month, but is expected to encounter stiff opposition from the White House and on the Senate floor.

“Just because there are deficiencies in the law … that can’t serve as an excuse for criminal actions like this to be unpunished,” said Rep. Price. “I hope the new attorney general makes this case a top priority. He needs to announce to the American people and the world that we uphold the rule of law and we intend to pursue this.”

Mr Price said that, while the contractors cannot be tried under his legislation retrospectively, they could be brought to justice under the War Crimes Act or other legislation.