Tuesday's session ended with fierce confrontation between Saddam and the judge. Saddam labelled the trial as "unfair", and threatened not to attend Wednesday's session.
"I will not attend an unfair trail," Saddam said.
Two more "complainants" will be heard during the initial phase of the trial dedicated to hearing the case against Saddam and seven of his former aides, over the execution of 148 Shia villagers who allegedly participated in an assassination attempt against Saddam in the early 1980s.
With only two witnesses to appear, Wednesday's session is likely to be short, after which the trial is expected to be adjourned for at least several weeks, as the country concentrates on legislative elections set for 15 December.
Early in the morning, 20 attackers stormed a hospital in the northern city of Kirkuk to free a detainee said to be part of an assassination plot against one of the judges trying the case, killing three policeman in the process.
Police had arrested the detainee with 11 other members of an Islamist cell linked to al-Qaida that had planned to murder Raed al-Juhi this week.
Barzan al-Tikriti, former director
of Iraq's intelligence service
The Saddam trial has been plagued by problems since its inception, most notably over security. Two defence lawyers have already been murdered.
During the fourth session on Tuesday, witnesses testifying behind a screen, with electronically distorted voices, described being beaten, pistol whipped and given electric shocks by Iraqi intelligence agents.
Their testimony was repeatedly challenged by defence lawyers and Saddam himself, who took the opportunity to make an outburst against the United States, Israel and the whole court. "Go to hell," were his parting words at the end of the hearing.
Saddam criticised the Kurdish presiding judge, Rizkar Mohammed Amin, accusing him of being taken in by American theatrics and scolding him for not being more concerned with the detention conditions of the defendants. He derided witnesses as "collaborators".
The defendants, who have all pleaded not guilty to charges including murder and torture, face the death penalty if convicted.
Tuesday's hearing began with "witness A" who gave disquieting testimony of how she was stripped naked and whipped by intelligence agents, before being thrown into Abu Ghraib jail in the early 1980s. Just metres away, Saddam sat quietly, occasionally blinking.
Throughout the day, the parade of anonymous witnesses continued, detailing the horrors allegedly inflicted upon them in the aftermath of a failed assassination attempt against Saddam in the village of al-Dujail in 1982.
The other witnesses spoke of being beaten, given electric shocks and kept in uncomfortable conditions with insufficient food.
Most witnesses spoke from
behind a screen
Saddam's half-brother Barzan al-Tikriti, who is suffering from cancer, interrupted the testimony, accusing one witness of not being clear on which security agency had interrogated them or in which building they were detained.
He charged that the man could not have actually seen him at these locations, although the witness insisted he saw the former director of the Mukhabarat intelligence service in al-Dujail.
During a lengthy session on Monday, Saddam again announced he was unafraid of being executed, as two witnesses appeared in full view and told of arrest, torture and abuse.
While many Iraqis, especially the Shia and Kurds who say they had been oppressed by Saddam, have called for a speedier trial, officials close to the tribunal say the court's deliberate pace is to try to ensure there is a fair trial.