Homicide bombers killed 22 people in the Baghdad (search) area Sunday, as insurgents stepped up a relentless campaign that claimed more than 90 lives a night before in a bombing near a Shiite mosque south of the capital.

The Iraqi Special Tribunal (search) filed its first criminal case against Saddam Hussein for a 1982 massacre of Shiites and said a trial date would be set within days, despite U.S. fears a trial would inflame tensions at a time the Shiite-led government is trying to lure Sunnis away from the insurgency.

In the past week alone, at least 170 people were killed in homicide bomb attacks throughout Iraq.

Three U.S. soldiers were killed over the weekend, including one on Sunday when a homemade bomb exploded in central Iraq, the military said. At least 1,766 members of the U.S. military have died since the Iraq war started in March 2003, according to an Associated Press count.

Elsewhere, one car bomber Sunday struck the offices of Iraq's electoral commission in eastern Baghdad, killing five election employees and one policeman. The commission said in a statement that it "affirms its determination to continue the electoral process," including plans for a national referendum on a new constitution and balloting for a new government later this year.

In another homicide attack, insurgents dumped two bodies on the road, then struck police who stopped to inspect them, the U.S. military said. Two policemen and one civilian were killed in the explosion.

About an hour later a suicide car bomber attacked a police convoy near a bus station in southern Baghdad, killing three police commandos and four civilians, police Capt. Talib Thamir said.
Another suicide car bomber missed a U.S. convoy but blasted two minibuses, killing six civilians in Mahmoudiya (search), about 20 miles south of Baghdad, police Capt. Rashid al-Samarie said.

In Baghdad, Raid Juhi, chief judge of the tribunal, announced the first criminal case has been filed against Saddam, stemming from the 1982 massacre of an estimated 150 Shiites in retaliation for a failed assassination attempt.

Juhi said the investigation into the July 8, 1982, massacre in Dujail, 50 miles north of Baghdad, has been completed, and the case was referred to the courts for trial. The step roughly corresponds to an indictment in the U.S. legal system.

The date for the trial of Saddam and three others was expected to be determined in "the coming days," Juhi said. If convicted, the four could face the death penalty.

Some U.S. officials have quietly urged the Iraqis to proceed carefully in prosecuting Saddam as the Shiite-led government seeks to draw Sunnis away from the insurgency.

Those overtures have been impeded by a sharp rise in suicide bombings, which have taken a toll on Iraqi civilians.

The weekend's most devastating attack occurred in Musayyib, 40 miles south of Baghdad, where a homicide bombing ignited a fuel truck in front of a Shiite mosque as thousands were strolling through nearby markets in the cool of the evening or heading for sunset prayers.

The Iraqi government reported Sunday that the death toll stood at "more than 90," and hospital officials said more than 150 were injured. It was the second deadliest single bombing since the Saddam Hussein was driven from power in April 2003 — exceeded only by a Feb. 28 suicide car bombing in Hillah that killed 125.

An Aug. 29, 2003, car bomb outside a mosque in Najaf killed more than 85, but a definitive death toll was never released.

"The Iraqi government condemns this brutal attack and promises the Iraqi people it will continue to tighten the grip on the terrorist organization by improving our armed forces and regaining control of security," the government said in a statement Sunday.

A day after the carnage, dazed survivors and relatives wandered through the charred wreckage. Some wept as they lifted blankets covering blackened bodies of victims. One weeping man struck himself in the head as a sign of grief. A woman shrouded in black screamed as she walked by the bombing site.

Several men carried wooden coffins on their shoulders, leaving the scene where nearly all building fronts had been damaged. One charred shoe was left in the street, near a pool of dried blood mixed with ashes. A blackened bicycle also lay abandoned close to a truck hitched to a fuel tanker that may have fed the blaze.

In a message of condolence, Iraqi President Jalal Talabani said that "after running out of their pretexts of resisting the occupation," the insurgents "have been targeting religious places, children, oil and water facilities and Iraqi soldiers."

Witnesses and police gave conflicting accounts of the bombing since many of those who were closest doubtless perished in the inferno. Most said a fuel tanker was moving slowly in the center of the town when the blast occurred, but a tanker truck in the area was mostly intact Sunday.

Zeyd Mohammed, 25, said a tanker truck filled with fuel detonated as it approached the mosque.

"The truck was moving when the suicide attacker detonated himself. He was targeting the mosque," Mohammed said.

Musayyib, on the Euphrates River, sits in the "triangle of death," an area so-named because of the large number of kidnappings and killings of Shiite Muslims traveling between Baghdad and the holy cities of Karbala and Najaf.

The military said a U.S. soldier was killed and two others were wounded Sunday in the bombing near Balad, 50 miles north of Baghdad.

Another soldier was killed and two wounded in a bomb attack Saturday near Kirkuk. A U.S. soldier assigned to the 155th Brigade Combat Team of the II Marine Expeditionary Force also died Saturday of wounds from a car bomb attack the day before in Iskandariyah.