BAGHDAD, Iraq -- Iraqi leaders named a tribunal of judges and prosecutors to try Saddam Hussein, placing a longtime opponent of the ousted dictator in the forefront of the case against him and his former Baathist inner circle, a spokesman announced Tuesday.

A senior member of Ahmad Chalabi's Iraqi National Congress was appointed to head the all-Iraqi tribunal -- a potentially controversial choice.

Chalabi, a longtime exile who returned to Iraq and was named to the U.S.-appointed Iraqi Governing Council, is mistrusted as an outsider by many Iraqis who want to see Saddam prosecuted by Iraqis who were present under his brutal rule.

In the tribunal appointments, Salem Chalabi, a U.S.-educated lawyer and nephew of Ahmad Chalabi, was named by the Governing Council as director-general of the court, said INC spokesman Entefadh Qanbar. He named seven judges and four prosecutors, and further judges will be appointed, Qanbar said. No date has been set for the trial.

On Tuesday, guerrillas fired a barrage of mortar rounds at Baghdad's largest prison, killing 22 prisoners in an attack a U.S. general said may have been an attempt to spark an inmate uprising against American guards. The slain prisoners were all security detainees, meaning they were suspected of belonging to the anti-U.S. insurgency or to Saddam's former regime.

Tuesday's attack was the bloodiest against the prison complex of Abu Ghraib in western Baghdad. Ninety-two prisoners were wounded, 25 of them seriously, said Col. Jill Morgenthaler, a U.S. military spokeswoman.

"This isn't the first time that we have seen this kind of attack. We don't know if they are trying to inspire an uprising or a prison break," Brig. Gen. Mark Kimmitt told AP.