BAGHDAD, Iraq (CNN) -- A roadside bomb exploded near an Iraqi army patrol near a restaurant in western Baghdad's al-Mansour district.
Also Sunday, in Iraq's Diyala province, at least four people were killed and 17 others wounded in several attacks, a security official in the province said.
The attacks came as Iraqis prepared for Eid al-Fitr, which marks the end of Ramadan with feasts and celebrations. The holiday in Iraq begins Tuesday.
In Baghdad's central Karrada district, a suicide bomber wearing an explosives vest detonated minutes after a bomb in a parked car exploded, the Interior Ministry's head of Explosives and Ordnance Disposal unit said, speaking on state-run al-Iraqia television.
Twenty people were killed and 72 wounded in those attacks, which occurred in a busy commercial area in Karrada. Three women and four policemen were among the dead, and the wounded included seven policemen and women and children, the Interior Ministry said.
Initially, the Interior Ministry reported a roadside bomb followed the car bomb. But Iraqi Gen. Jihad al-Jabiri of the Interior Ministry later said that as people gathered about 328 feet (100 meters) from where the car had exploded, the suicide bomber detonated amid the crowd, causing most of the casualties.
Earlier Sunday, a bomb detonated in a car parked near a southwestern Baghdad market and mosque, killing at least a dozen people and wounding 35 others, the official said. The attack, which occurred shortly before Iftar -- the evening meal at which Muslims break their fast during Ramadan -- took place in a predominantly Shiite area.
Around the same time, a bomb attached to a car detonated on a bridge in southwestern Baghdad, killing the driver and wounding a civilian bystander, the official said. It was believed the bomb was attached to the car without the driver's knowledge, the official said.
Earlier Sunday, a roadside bomb exploded near an Iraqi army patrol close to a restaurant in western Baghdad's al-Mansour district, killing one soldier and wounding three others.
In Diyala province, a roadside bomb struck an Iraqi Army patrol in Balad Ruz Sunday morning, killing at least two soldiers and wounding 10 others, a security official in the province said. Balad Ruz is about 30 miles (48 kilometers) east of the provincial capital of Baquba.
In Diyala's Khan Bani Saad, near Baquba, gunmen opened fire on civilians Sunday and killed at least two people, the official said.
And in central al-Saadiya -- a predominantly Kurdish town northeast of Baquba -- a roadside bomb struck the convoy of Ahmed al-Zarqoushi, the town's mayor. The attack wounded al-Zarqoushi and seven others, including five members of his security detail and two civilian bystanders.
Al-Saadiya is close to Khanaqin, a predominantly Kurdish area of the province in dispute between the central government and the autonomous Kurdish regional government in northern Iraq.
On Friday, Maj. Gen. Jeffrey Hammond, the U.S. commander in Baghdad, said violence in Baghdad during Ramadan had dropped sharply from last year, when 600 attacks occurred. This year, not including the attacks this weekend, Baghdad had experienced about one-tenth of that number, he said.
About 800 attacks took place in Baghdad during Ramadan in 2006, he said.