A suicide car bombing Friday night near President Jalal Talabani's official residence capped a day of explosions across the capital in which at least 25 people were killed, including policemen, security guards and civilians, and 111 others were wounded.

At least seven of the attacks were suicide bombings. One struck an Iraqi army base in the Shaab district, killing eight Iraqis and wounding 20, according to Iraqi officials. Another in the Sadiya district killed 11 people and wounded 24. After nightfall, a car bomb in western Baghdad killed six policemen and wounded 45 people, most of them civilians, Iraqi police reported.

Three American soldiers were wounded but none died in the attacks, U.S. military spokesmen said. However, two Marines were killed in a roadside bombing during combat operations in a desert area of western Iraq near the Jordanian border, according to a statement by U.S. military officials.

Accounts provided by Iraqi police, the U.S. military and news services during a day of confusing and fast-moving events gave conflicting information on the number of attacks and casualties in the Baghdad area.

But the wave of violence, which stretched from morning until after dark, came in sharp contrast to the relative lull that had followed a six-week offensive against insurgents by the U.S. and Iraqi militaries.

"The terrorists continue to strike at the most innocent," said Col. Joseph DiSalvo, commander of U.S. forces in eastern Baghdad. "There is no place in civilized society for these murderers."

The day's final bombing near Talabani's residence was carried out on the al-Hussein Bridge, a double-decked span across the Tigris River that links the working class neighborhood of Doura with the upscale Jadriyah section, where the presidential residence is located.

A policeman at the scene who declined to give his name would confirm only that a bomb had exploded on the bridge, but the Associated Press reported that three of Talabani's guards were killed. It was not immediately clear whether Talabani was at home when the bomb went off at about 8 p.m.

The flurry of attacks made Friday the third day this week in which suicide bombings killed more than 20 people in Baghdad. On Sunday, a lone suicide bomber killed 21 men waiting outside a military recruiting base near the center of the city, and on Wednesday a suicide car bomb killed 27 people -- including more than a dozen children and one U.S. soldier -- in eastern Baghdad.

Last week, a top U.S. commander and Iraq's interior minister said in separate news conferences that car bombings had been reduced by half in Baghdad and that insurgents' ability to sustain bombing campaigns had been diminished by a security crackdown, officially called Operation Lightning.

Al Qaeda's Iraq wing claimed responsibility for Friday's first five bombings, including the attack in Shaab. A statement from the group said that "a lion from our brigade" had "staged a heroic attack on a unit of the apostate [Iraqi] guard."

That bombing destroyed several cars and left bystanders soaked in blood, witnesses said. One told the Reuters news agency that he saw army vehicles parking near an army facility when a Daewoo car approached at high speed, exploded and "split in two."

In other attacks around Baghdad on Friday, officials said, two people were killed and at least 14 were wounded when a car bomb exploded near a building that formerly housed the Defense Ministry in Bab al-Muadham, and two people died and seven were injured when another car exploded near an Iraqi patrol in Andalus Square.

Outside Baghdad, a suicide bomber blew himself up while trying to assault a Shiite mosque south of Babel. Another bomb killed five Iraqi soldiers and one civilian, and wounded 17 civilians, in Haswa, 30 miles south of the capital.

Special correspondent Naseer Nouri contributed to this report.

A column of smoke rises from a car bomb attack on an Iraqi army convoy, which wounded five soldiers and three civilians in Baghdad.