Soldier after soldier took the witness stand Monday and told of being shredded by exploding grenades or shot, of tents burning, of troops strapping on gas masks, of medevac helicopters and the screams of dying men.

"I was immediately hurled in the air and ... before I hit the ground I said to myself, 'You've lost your left leg,' " Capt. Andros Marton testified.

It wasn't the enemy attacking, though; it was one of their own. Sgt. Hasan Akbar of the 101st Airborne Division attacked three tents at a desert camp in Kuwait the night before his unit was supposed to join the invasion of Iraq.

The prosecution and defense agreed on that much Monday in the first day of testimony in Akbar's court-martial on two counts of premeditated murder and three of attempted premeditated murder.

The defense, though, said it would prove that his long-standing mental illness made it impossible for the killings to be premeditated.

Akbar is the first soldier since the Vietnam era to be tried for killing a fellow soldier during a time of war. He could face the death penalty.

Army Capt. Christopher S. Seifert died in the attack, and 15 other soldiers of the 101st Airborne Division's 1st Brigade combat team were hurt. One, Air Force Maj. Gregory L. Stone, later died of his wounds.

As war approached, Akbar, a Muslim, was so confused that he thought the slurs used among the soldiers to describe Iraqis were threats directed at him, and that sick jokes among his fellow soldiers about raping Iraqi women were real military plans, one of his attorneys said in an opening statement.

"When Sgt. Akbar acted, it was out of desperation, fear and confusion," Maj. Dan Brookhart said.

Odd behavior

Akbar, 33, came from a family with a history of mental illness and was diagnosed himself at age 14. His problems, which include depression, have worsened since then, Brookhart said.

Witnesses from different points in his life, from childhood until his deployment to Kuwait, will testify that he behaved oddly, Brookhart said.

A loner, Akbar has long been known for things such as pacing, talking to himself, getting angry at unimportant incidents that are years old, and smiling and laughing for no apparent reason. He was so ill, in fact, that he had become an incompetent soldier, Brookhart said. Five minutes after being issued an order, he would forget it.

Akbar was essentially fired as a team leader, and his unit had decided not to take him on its planned assault by air into Iraq because of his behavior, Brookhart said.

Upset by the rough talk and dehumanizing slurs the troops had started using for Iraqis, Brookhart said, Akbar called one of his sergeants late one night just before the unit left for Iraq. He had one question: "Are we really going to be raping the Iraqi women?"

It's also public knowledge that Akbar has a sleep disorder. He frequently fell asleep in earlier court proceedings. Brookhart said that was yet another recognized symptom of mental illness.

Akbar hasn't been a model prisoner. Before a pretrial hearing in March, he struggled with one of the military police escorts taking him to court. Now he comes to court in shackles.

Accused of planning

In the prosecution's opening statement, Capt. John Benson chopped his hand at the seated defendant as he named him and vowed to prove that the killings were premeditated. Evidence of this includes entries in Akbar's diary, he said.

Benson evoked the feeling of apprehension at the beginning of the invasion. "What the soldiers of the 1st Brigade combat team did not know, what they could not ... was that their enemy was already inside the wire," he said.

Benson detailed Akbar's attack on March 23, 2003. He described how the sergeant stole grenades from a Humvee he was supposed to be guarding, tripped a switch on a generator to kill the lights, and then moved to a tent where many of the brigade's leaders slept and flung a grenade inside. He moved to another tent, the one where Stone and other soldiers were sleeping, and tossed another grenade.

After an explosion, Lt. Col. (then Maj.) Kenneth Romaine burst out of the tent with his pistol drawn, saw Akbar and told him to halt, Benson said. Akbar shot him in the hands and moved on to a third tent, where he saw Seifert outside and shot him in the back.

Explosive residue on Akbar's uniform was consistent with hand grenades, tests showed his gun was the one used to kill Seifert, and his fingerprints were on the generator, Benson said.

Even though the defense isn't contesting Akbar's role in the events, Benson called more than a dozen witnesses who were in the camp that night to give the details. The defense had only a couple of minor questions for the witnesses.

Several of the witnesses had been asleep in the same tent as Stone.

Mark Wisher, an Air Force captain attached to the unit for the invasion, described the sound of a grenade hitting the floor near him, and of instinctively moving away from it before being blown into the air and bouncing off the inside of the tent. Then he told of cradling the mortally wounded Stone, who he called by Stone's aviation call sign, "Linus."

"I noticed he was having trouble breathing," Wisher said. "I told him, 'Hang with it, Linus, hang with it; you're going to make it.' "

Wisher's voice softened.

"I finally realized that some medic wasn't just going to magically appear," he said. "I just said, 'Can somebody help me please?' "

Someone came up, he asked for a compress, and the soldier retrieved a T-shirt that Wisher held against Stone's neck for several minutes.

Then he started to feel the effects of his own wounds, which included holes in his hands, arm and shoulder, a lacerated liver and a collapsed lung. Someone took over first aid on Stone. Wisher, struggling to breathe, started to feel lightheaded. First he sat in the middle of the tent, then he sank to the floor.

The court-martial continues today. Fort Bragg officials say it could last two weeks or up to five.

At the end, the 15 jurors -- all officers and senior noncommissioned officers -- don't have to be unanimous on the lesser charge, but it would take a majority of two-thirds to convict Akbar.

For premeditated murder, the vote must be unanimous. For the jury to impose the death penalty would require two more unanimous votes: first on whether the case meets the qualifications and then on the penalty itself.