The caped figure on the surveillance video came running out of the darkness to the edge of a remote Army outpost in southern Afghanistan. Blood was smeared on his face, prosecutors said, and soaked into his clothes.
Less than a mile away, 16 Afghans, including nine children, were dead, some of their bodies on fire in two villages.
As fellow soldiers stopped him at the base's gate, Staff Sgt. Robert Bales was incredulous, prosecutors said. Then, as he was taken into custody, Bales said, "I thought I was doing the right thing."
The details, from a prosecutor as well as Bales' comrades, emerged Monday as a preliminary hearing in his case opened, offering the clearest picture yet of one of the worst atrocities of the Iraq and Afghanistan wars.
The March 11 attack prompted the U.S. to halt combat operations for days in the face of protests, and it was a month before military investigators could reach the crime scenes.
The prosecutor, Lt. Col. Jay Morse, said that after Bales attacked one village near his post at Camp Belambay, he returned, woke a colleague to report what he had done, and warned that he was headed back out to attack another village.
"I never got out of bed, sir," the colleague, Sgt. Jason McLaughlin, testified. "I thought it was ridiculously out of the realm of normal possibility, sir."
Bales, 39, faces 16 counts of premeditated murder and six counts of attempted murder. The hearing could last up to two weeks and will help determine whether the case goes to a court martial.
The defense did not give an opening statement.
Bales has not entered a plea. His attorneys have not discussed the evidence but say Bales has post-traumatic stress disorder and suffered a concussive head injury during a prior deployment to Iraq.
The father of two from Lake Tapps, Wash., wore green fatigues and sat beside one of his civilian lawyers as an investigating officer read the charges against him and informed him of his rights.
When asked if he understood them, Bales said, "Sir, yes, sir."
Bales spent the March night before the raids at Camp Belambay, watching "Man On Fire," a fictional account of a former CIA operative on a revenge spree, with his fellow soldiers, Morse said.
He seemed normal as they shared whiskey, discussed Bales' anxiety over whether he'd get a promotion and talked about another soldier who lost his leg a week earlier in a roadside bomb attack, Cpl. David Godwin testified.
Shortly before leaving the base, Bales told a Special Forces soldier that he was unhappy with his family life and that the troops should have been quicker to retaliate for the March 5 bomb attack, Morse said.
"At all times, he had a clear understanding of what he was doing and what he had done," said Morse, who described Bales as lucid and responsive.
Bales is accused of slipping away from the remote outpost with an M4 rifle outfitted with a grenade launcher to attack the villages of Balandi and Alkozai, in a dangerous district.
Prosecutors played for the first time the video captured by a surveillance blimp that showed the caped figure running toward the base, then stopping and dropping his weapons as he was confronted. There was no audio.
It wasn't immediately clear from where Bales got the cape.
As he stood outside the base, Godwin testified, Bales had asked him and another soldier: "Did you rat me out? Did you rat me out?"
Part of the hearing will be held overnight to allow video testimony from witnesses, including an estimated 10 to 15 Afghans, in Afghanistan.
Bales' attorney, John Henry Browne, said the hearing will give the defense a chance to see what the military can prove. He said they are expecting a court martial.
The Ohio native joined the Army in late 2001 — after the 9/11 attacks — as his career as a stockbroker imploded, including an arbitrator's $1.5 million fraud judgment against him and his former company.
Bales was serving his fourth combat tour after three stints in Iraq and his arrest prompted a national discussion about the stresses that soldiers face from multiple deployments.
His lawyers have said Bales remembers little or nothing from around the time of the attacks.
Emma Scanlan, one of his attorneys, declined to say to what extent the lawyers hope to elicit testimony that could be used to support a mental-health defense. Bales himself will not make any statements.
She said the Army had only recently turned over a preliminary DNA trace evidence report from the crime scenes, but defense experts have not had time to review it.