One of four soldiers charged with pushing two Iraqi civilians into a river, where one of them drowned, says he was ordered to do so and told what to say to officials looking into the death, an Army investigator testified Wednesday.

Spc. Terry Bowman said he "was told by his chain of command what version to give" investigators, Sgt. Irene Cintron of the Army's Criminal Investigation Command (search) said during a teleconference from Iraq as the military convened a hearing to determine whether the soldiers will be court-martialed.

Bowman said he had been ordered to push the men into the Tigris River (search), Cintron said.

It was not disclosed who gave the order. Three of the soldiers' commanders have received nonjudicial punishments for their roles in the incident. None of those punishments include jail time.

Defense attorneys, questioning the strength of the Army's case, said investigators relied only on relatives in concluding it was Zaidoun Fadel Hassoun, 19, who drowned. They said insurgents have frequently faked deaths to embarrass U.S. forces and get soldiers into trouble.

Cintron said investigators were told by Hassoun family and Iraqi civil defense forces a body was found, but conceded security concerns prevented her from going to the scene to verify the claim. She said no autopsy was conducted and no body has been exhumed.

Sgt. 1st Class Tracy E. Perkins, 33, 1st Lt. Jack M. Saville, 24, and Sgt. Reggie Martinez, 24, are charged with involuntary manslaughter in the Jan. 3 drowning death of the man identified by family members as Hassoun.

Bowman, 21, is charged with assault for allegedly pushing the second man into the river at the same time. That man, a cousin of Hassoun named Marwan Fadel Hassoun, 23, survived the incident and had described the events to The Associated Press.

Marwan Hassoun said he tried to help his cousin swim to safety, only to lose his grip as the soldiers watched and laughed. "They were behaving like they were watching a comedy on stage," he told the AP several weeks ago.

Attorneys said troops in Iraq have not been able to locate Marwan Hassoun to get a sworn statement.

Perkins, Martinez and Bowman appeared at Wednesday's Article 32 hearing, which is similar to a civilian grand jury hearing. Saville's hearing is tentatively scheduled for Sept. 9. The four soldiers face between 5 1/2 years and 26 1/2 years in prison if they are tried and convicted.

According to Cintron, investigators learned of the death in an e-mail from the victim's family. She said she met with Marwan Hassoun on Jan. 16; he told her how they were stopped after getting supplies in Baghdad and then driven to the bridge several miles north of Samarra.

Marwan Hassoun said he watched the soldiers push his cousin into the water and then he was pushed in, Cintron testified. He said he could hear his cousin screaming.

"He said it was eight meters (24 feet) deep and at no point did he feel the bottom of the river," she said. She described the drop from the bridge as 10-12 feet.

After he got out on the bank, Hassoun said he could hear the soldiers above laughing as they drove away. He said he went back to a checkpoint "soaking wet from the river" and reported what happened, Cintron said.

A body was found two or three miles downriver.

Martinez initially told investigators neither he nor anyone in his platoon pushed anyone in the river, Cintron said. A week later, on Jan. 23, Martinez said he had gone to the river's edge with the men, "kicked one in the butt" but the man jumped in on his own.

Sgt. Alexis Rincon, a member of the patrol that night, testified the soldiers forced the men to jump and that Martinez leveled a rifle at one of them. Rincon said the man hesitated, but jumped after the second Iraqi said something to him in Arabic.

None of soldiers thought the men were in danger because one quickly made it to shore, Rincon said. He said he would not have left the scene had he known one of the men was drowning, but asked if he would have gone to the man's aid, Rincon replied: "I don't know about jumping in and saving him."

The soldiers' commanders, Lt. Col. Nathan Sassaman, Maj. Robert Gwinner and Capt. Matthew Cunningham, were punished last spring under Article 15, which allows punishments without a court proceeding or public record.