Like most Iraqis, Mohammad Abood expects the highly secured roads at the Baghdad airport to be safe. So when someone told him his father's car had broken down on his way to a job in the terminal, the son calmly went to assist him. But a cordon of U.S. troops stopped him from reaching the car. Abood, 21, could only get close enough to see the two-door Opel engulfed in flames, incinerating 57-year-old Hafd Abood and two women colleagues from his office in an airport bank. Abood realized the breakdown story had been a friend's way of easing him toward the tragedy. "I couldn't bear it. My father was inside, burning," Abood recalled, describing how he beat himself and fell on the ground in anguish before the soldiers ordered him to stay away.

The next day, the family recovered the carbonized body of Hafd, a gentle man who used to come home and tutor his children, urging them to focus on schooling. His death has prompted outrage from co-workers and the country's political elite, who are in the middle of negotiating with Americans over the future of U.S. troops in Iraq. Last week, Iraqi Prime Minister Nuri al-Maliki called for a special investigation into the June 25 shooting—though he's launched similar probes in other deaths with little result.

The U.S. military issued a press release the day of the shooting. It said troops from the 4th Brigade Combat Team, 10th Mountain Division, were stopped on the roadside when "criminals" traveling the road fired on them. When the soldiers fired back, the statement said, the car crashed against a wall and "exploded." Two of the U.S. vehicles had bullet holes and a weapon was found in the burned car according to the military.

The statement provokes anger from Hafd Abood's friends and relatives and, at the very least, leaves many questions unanswered. Those killed were all longtime bank workers on their usual morning commute. The spot where the shooting occurred is supposed to be one of the safest in Iraq. By most accounts, including a police document shown to NEWSWEEK, it occurred inside the extensive campus of the Baghdad International Airport, a presumed secure zone. Travelers and airport workers get searched in a series of checkpoints as they enter from the notorious airport highway. Guards watch security contractors to ensure they unload their weapons for the last couple miles on the loop around to the commercial terminal. It's where the dangers melt away and you can finally relax.

Airport police, who spoke to NEWSWEEK on the condition they not be named, said they believe that Hafd Abood was unarmed, having successfully passed through checkpoints that include a bomb-sniffing dog. Their theory is that he was about 30 yards from the parked soldiers when he swerved in their direction to avoid a large pothole. Another motorist, refusing to be identified because of the intense attention the case is receiving, told NEWSWEEK that the soldiers fired into his hood to keep him away from where they were positioned, apparently after they had already shot Hafd Abood's car.

Military spokesman Lt. Col. Steven Stover reiterated the account in the original press release and said an officer was investigating the incident—a standard procedure. In an email, he said the troops involved were staying on their Camp Victory base in the meantime. He said the military had photographs showing the bullet damage to the vehicles, but he would not release them since they are part of the probe. He confirmed that a man and two women were killed and said the investigation was ongoing as of Monday night.

Iraqis say the women were Maha Adnan Younis and Surur Shahid Ahmed, both in their 30s. The Iraqi police called the shooting "unjustifiable" and challenged the U.S. investigators to disclose the photos or show spent casings from any enemy rounds fired at the soldiers. Mohammed Abood said his father's car appeared to have burned but did not appear damaged as it might after an accident or explosion.

Such shootings have happened often during the five years of war, in which troops at risk of car bombs or gunfire have to operate in proximity to civilians. But this case—especially hard to explain because of the location and the nature of the victims—comes as Iraqis and Americans are hashing out the rules troops will operate under in the future and, possibly, how long they will stay in Iraq. The self-imposed deadline for a so-called "Status of Forces Agreement" is July 31, but Iraqi officials are increasingly saying it may be finished late or not at all. In interviews last week, several said the airport shooting raised the political heat against the American presence. A parliamentary committee discussed the case and Maliki was briefing top officials about it.

Like many Shiite Muslims, Hafd Abood was overjoyed when the 2003 American invasion toppled Saddam Hussein, according to another son, Zeaad Abood, 27, who followed his father's advice about education to become a biologist. "Whenever people spoke against the Americans, he would defend them," remembers Zeaad. Whatever happened on the airport access road that morning, Iraqis now find that defense a lot harder to make.

With Yassar Ghani, Salih Mehdi and Hassan Al-Jarrah in Baghdad