In a remote and dangerous corner of Afghanistan, under the protective roar of Apache attack helicopters and B-52 bombers, special agents and investigators did their work.

They walked the landscape with surviving witnesses. They found a rock stained with the blood of the victim. They re-enacted the killings — here the U.S. Army Rangers swept through the canyon in their Humvee, blasting away; here the doomed man waved his arms, pleading for recognition as a friend, not an enemy.

“Cease fire, friendlies, I am Pat [expletive] Tillman, damn it!” the NFL star shouted, again and again.

The latest inquiry into Tillman’s death by friendly fire should end next month; authorities have said they intend to release to the public only a synopsis of their report. But the Associated Press has combed through the results of 2 1/4 years of investigations — reviewed thousands of pages of internal Army documents, interviewed dozens of people familiar with the case — and uncovered some startling findings.

One of the four shooters, Staff Sergeant Trevor Alders, had recently had PRK laser eye surgery. He said although he could see two sets of hands “straight up,” his vision was “hazy.” In the absence of “friendly identifying signals,” he assumed Tillman and an allied Afghan who also was killed were enemy.

Another, Specialist Steve Elliott, said he was “excited” by the sight of rifles, muzzle flashes, and “shapes.” A third, Specialist Stephen Ashpole, said he saw two figures, and just aimed where everyone else was shooting.

Squad leader Sergeant Greg Baker had 20–20 eyesight, but he claimed he had “tunnel vision.”

Amid the chaos and pumping adrenaline, Sergeant Baker said he hammered what he thought was the enemy but was actually the allied Afghan fighter next to Tillman who was trying to give the Americans cover: “I zoned in on him because I could see the AK-47. I focused only on him.”

All four failed to identify their targets before firing, a direct violation of the fire discipline techniques drilled into every soldier.

There’s more:

• Tillman’s platoon had nearly run out of vital supplies, according to one of the shooters. They were down to the water in their CamelBak drinking pouches, and were forced to buy a goat from a local vendor. Delayed supply flights contributed to the hunger, fatigue, and possibly misjudgments by platoon members.

• A key commander in the events that led to Tillman’s death both was reprimanded for his role and meted out punishments to those who fired, raising questions of conflict of interest.

• A field hospital report says someone tried to jump-start Tillman’s heart with CPR hours after his head had been partly blown off and his corpse wrapped in a poncho; key evidence including Tillman’s body armor and uniform was burned.

• Investigators have been stymied because some of those involved now have lawyers and refused to cooperate, and other soldiers who were at the scene couldn’t be located.

• Three of the four shooters are now out of the Army, and essentially beyond the reach of military justice.

Taken together, these findings raise more questions than they answer, in a case that already had veered from suggestions that it all was a result of the “fog of war” to insinuations that criminal acts were to blame.