Testifying under immunity, three U.S. Army commanders admitted Friday that soldiers were told to cover up an incident in which two Iraqi civilians were forced off a bridge into the Tigris River (search), where family members say one of them drowned. The commanders, however, said they don't believe anyone died, despite what the family and prosecutors say.

Capt. Matthew Cunningham said soldiers under his command admitted they forced the Iraqis to jump into the river last Jan. 3. He said the soldiers told him they had the Iraqis "get wet" and that "they wanted to make them miserable a little bit and walk home."

He said it was a bad decision, but that soldiers had to have non-lethal ways to make their presence felt in the area. He called the suggestion that anyone drowned a "smear campaign" and said soldiers saw the civilians getting out of the river safely.

Cunningham also testified that he and other commanders told the soldiers to clam up because they feared higher-ups in the chain of command would use the incident against them.

"We were not covering up anything that injured anybody," he said.

The testimony came on the third and final day of a hearing to determine whether three soldiers will be court-martialed (search) in the incident. Family members in Iraq say Zaidoun Hassoun, 19, drowned and they will exhume his body to prove it; a cousin survived.

Sgt. 1st Class Tracy E. Perkins, 33, and Sgt. Reggie Martinez, 24, are charged with involuntary manslaughter, as is 1st Lt. Jack M. Saville, 24, whose hearing will be held later. The third defendant at this week's hearing, Spec. Terry Bowman, 21, is charged with assault for allegedly pushing the cousin into the river.

The Article 32 hearing (search) is similar to a civilian grand jury session. The hearing officer, Capt. Robert Ayers, will make a recommendation later on whether the men should face a court-martial. The four soldiers face 51/2 years to 261/2 years in prison if they are convicted.

Cunningham, a company commander in the brigade, testified along with deputy battalion commander, Maj. Robert Gwinner, and battalion commander Lt. Col. Nathan Sassaman. All three were granted immunity in return for their testimony.

Gwinner said the incident was the result of clash between Sassaman and the brigade's then-commander, Col. Frederick Rudesheim.

Gwinner said Sassaman instructed soldiers not to tell investigators they had forced the Iraqis to jump in the river because he was concerned the investigation was "a personal vendetta between he and Col. Rudesheim." Gwinner said the brigade commander was jealous of Sassaman, a former star quarterback at West Point, because he was very aggressive and getting lots of television coverage.

Like Friday's witnesses, defense attorneys argue that there is evidence that no one actually drowned on Jan. 3. The defense attorneys said insurgents have frequently faked deaths to embarrass U.S. forces and get soldiers into trouble.

On Wednesday and Thursday, they produced as witnesses three soldiers who say they saw two civilians climbing up the riverbank. All three said they were able to tell the two were civilians through their night vision goggles because they were not wearing flak jackets or carrying weapons.

Family members, however, say Zaidoun Hassoun drowned that night and his body was found downriver 13 days later. The survivor, Marwan Fadel Hassoun, 23, has told The Associated Press he tried to save his cousin's life as soldiers watched and laughed from the bridge above.

An uncle, Nizar Fadhel al-Samarrai, told the AP that Army investigators never showed up to confirm the death of his nephew, though the family was prepared to exhume the body to prove it.

Army investigator Sgt. Irene Cintron testified that it was too dangerous to exhume the body, and she relied on the word of family members and members of the Iraqi Civil Defense Force.

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