The appeals court in Iraq should rule on Saddam Hussein's guilty verdict and death sentence by the middle of January, the chief prosecutor said Monday, setting in motion a possible execution by mid-February.

Chief prosecutor Jaafar Moussawi said the appeals court would act quickly because it had no other cases under consideration.

"The appeals panel will take less than a month to make its decision," Moussawi said. The hanging must be carried out within 30 days of the ruling.

Shiites marched in rallies in cities and towns across Iraq Monday to celebrate the ruling as Sunnis held defiant counter-demonstrations.

Despite a round-the-clock curfew imposed over the capital, witnesses said five mortars slammed into the Sunni neighborhood of Adhamiya. There were no immediate reports of damage or casualties.

Other parts of Baghdad were mostly quiet, with offices and the international airport closed and few cars or pedestrians on the streets. An Interior Ministry spokesman credited a round-the-clock curfew in Baghdad and two restive Sunni provinces.

Officials said the clampdown, which was also imposed in two volatile Sunni provinces, would likely be lifted by Tuesday morning.

"We need to keep on guard over any kind of response from Saddam supporters," Brig. Abdel-Karim Khalaf said.

Checkpoints were also closed along Iraq's border with Jordan and Syria, a standard precaution taken during domestic emergencies.

The U.S. military said Monday that two soldiers were killed when their helicopter crashed north of Baghdad and two Marines and a soldier were killed in fighting in the country's restive Anbar province.

In mainly Shiite Hillah, 60 miles south of Baghdad, around 500 people marched carrying placards and shouting slogans denouncing the former dictator, who is accused of killing tens of thousands of Shiites following a 1991 uprising.

"Yes, yes for the verdict, which we have long been waiting for!" chanted the crowd, largely made up of students and government workers.

Underscoring the widening divide between Shiite and Sunni, about 250 pro-Saddam demonstrators took to the streets in the Sunni city of Baqouba, 35 miles northeast of Baghdad. They were dispersed by Iraqi soldiers for breaking the curfew over the province. There were no reports of deaths or injuries.

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Another 400 protesters marched through Samarra, 60 miles north of Baghdad, denouncing the verdict against Saddam and demanding the ouster of Shiite Prime Minister Nouri al-Maliki, who had called for the former president's execution.

The curfew was temporarily lifted in Tikrit to give allow residents to shop and run errands. Angry crowds had gathered in the city on Sunday, holding aloft Saddam portraits, firing guns and chanting slogans vowing to avenge his execution.

Saddam was sentenced by the Iraqi High Tribunal for ordering the execution of nearly 150 Shiites from the city of Dujail following a 1982 attempt on his life.

If the appeals court upholds the sentences, all three members of the Presidential Council — President Jalal Talabani and Vice Presidents Tariq al-Hashimi and Adil Abdul-Mahdi — must sign death warrants before executions can be carried out.

But Talabani said Monday that while he had once signed an international petition against the death penalty, his signature was not needed to carry out the death sentence. Talabani, a Kurd, has permanently deputized Abdul-Mahdi, a Shiite Muslim, to sign on his behalf. Abdul-Mahdi has said he would sign Saddam's death warrant, meaning two of three signatures were assured.

Al-Hashimi, the other vice president and a Sunni Muslim, gave his word that he also would sign a Saddam death penalty sentence as part of the deal under which he got the job on April 22, according to witnesses at the meeting, which was attended by U.S. Ambassador Zalmay Khalilzad.

Saddam was found hiding with an unfired pistol in a hole in the ground near his home village north of Baghdad in December 2003, eight months after he fled the capital ahead of advancing American troops.

Barzan Ibrahim, Saddam's half brother and intelligence chief during the Dujail killings, was sentenced to join him on the gallows, as was Awad Hamed al-Bandar, head of Iraq's Revolutionary Court, which issued the death sentences against the Dujail residents.

Former vice president Taha Yassin Ramadan was convicted of premeditated murder and sentenced to life in prison, while three other defendants were given up to 15 years in prison for torture and premeditated murder. A local Baath Party official Mohammed Azawi Ali, was acquitted for lack of evidence.

The chief prosecutor in Saddam's separate trial for his crackdown against Iraqi Kurds in the late 1980s — the so-called Anfal case — will continue while the appeals court considers the death sentence rendered Sunday.

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Many European nations voiced opposition to the death sentences in the case, including France, Italy, the Netherlands, Spain and Sweden.

Islamic leaders warned that executing Saddam could inflame those who revile the U.S., undermining President Bush's policy in the Middle East and inspiring terrorists.

"This government will be responsible for the consequences, with the deaths of hundreds, thousands or even hundreds of thousands, whose blood will be shed," Salih al-Mutlaq, a Sunni political leader, told Al-Arabiya satellite television.

International legal experts said Saddam should be kept alive long enough to answer for other atrocities.

"The longer we can keep Saddam alive, the longer the tribunal can have to explore some of the other crimes involving hundreds of thousands of Iraqis," said Sonya Sceats, an international law expert at the Chatham House foreign affairs think tank in London.

The Associated Press contributed to this report.