WASHINGTON, Jan 17: The US Army may prosecute senior military officers for abuses at Baghdad's Abu Ghraib prison, lawyers involved in the proceedings told reporters.

The demand for bringing senior officers to court has strengthened since the sentencing on Saturday of an army reservist Charles Graner Jr, the alleged ringleader of the abuses at Abu Ghraib.

Graner, who was sentenced to 10 years in prison, told a military jury this weekend that he was following orders when he mistreated detainees. He also named several senior military officers who, according to him, had ordered guards like him to soften up the prisoners for interrogation.

Pictures of naked Iraqi detainees leashed and crawling, stacked in a pyramid and forced to perform sexual acts enraged the entire world when they appeared in international newspapers early last year.

US officials had hoped that by sentencing prison guards directly involved in the abuses, they would be able to improve America's image hurt by these pictures but the sentencing of reservists and junior officers has only increased the demand for more.

Last week, the New York-based Human Rights Watch demanded that a special prosecutor be appointed to probe policymakers like Defence Secretary Donald Rumsfeld for devising policies that led to these abuses.

A recent Pentagon inquiry found that senior military officials shared some of the responsibility," not only for failure to supervise and enforce discipline, but also in some cases for condoning or even encouraging mistreatment of detainees in cell blocks and during interrogations."

Also at Graner's trial, prosecutors did not deny sworn testimony that senior CIA and military officers asked prison guards to carry out questionable treatment, like striking detainees, using dogs to threaten them, and having female soldiers point and laugh as male detainees showered.

Several witnesses at the Graner trial testified that Col. Thomas Pappas, the highest-ranking military intelligence officer at Abu Ghraib, and Lt. Col. Steven Jordan, the head of the Joint Interrogation and Debriefing Center at the prison, had either known about or specifically encouraged tactics like using dogs to threaten detainees.

The two men were among five officers recommended for discipline in a Pentagon report in August, which said they bore responsibility for what happened even though they were not directly involved in abusing prisoners.

That report implicated 29 other military intelligence soldiers in at least 44 cases of abuse from July 2003 to February 2004, including one death, beatings, using dogs to threaten adolescent detainees, and having prisoners stripped naked and left for hours in dark, poorly ventilated cells that were stifling hot or freezing cold.

A classified portion of the report said Lt. Gen. Ricardo Sanchez, the former top commander in Iraq, approved the use there of some interrogation practices intended to be limited to captives held in Afghanistan and Guantánamo Bay, Cuba.