In the deadliest blast, a fuel tanker at a gas station was blown up by a suspected suicide attacker in western Baghdad, killing at least 50 people and wounding about 60 more, police said. The blast occurred in Mansour, a primarily Sunni neighborhood on the western side of the Iraqi capital.
Two police officers, both speaking on condition of anonymity out of security concerns, said the explosion was the work of a suicide attacker.
About four hours earlier a parked car bomb killed 17 civilians and left a gaping crater in a busy square in central Baghdad, police said.
Another 32 people were wounded by the blast, a police officer said on condition of anonymity out of security concerns.
An Associated Press reporter at the scene said the explosion ripped a hole one yard deep and 1 1/2 yards wide in the asphalt. Three minibuses and six cars were damaged by flames and flying debris. Blood pooled in the street.
The explosives had been planted in a vehicle in al-Hurriyah square in the mostly Shiite Karradah neighborhood, the police officer said.
U.S. military officials say three U.S. soldiers on patrol in eastern Baghdad died Tuesday when they were hit by a sophisticated armor-piercing bomb known as an EFP (explosively-formed penetrator). Six more troops were wounded in the attack.
Meanwhile, the head of Iraq's largest Sunni political bloc said Wednesday that Prime Minister Nouri al-Maliki had not met the group's demands and it would go ahead with a planned withdrawal from the Iraqi government.
The resignation of six Cabinet ministers from the Iraqi Accordance Front could erase the government's "national unity" status and diminish its legitimacy — a serious blow at a time when it needs to move swiftly on legislation the United States considers critical to reconciliation of Iraq's Shiite, Sunni Arab and Kurdish factions.
Adnan al-Dulaimi, head of the Accordance Front and a harsh critic of al-Maliki, told The Associated Press his bloc was "still insisting on withdrawing from the government if it doesn't meet our fair and objective demands."
"We don't want to take part in a government which claims it is a national unity one, but instead is sectarian rather than Iraqi," al-Dulaimi said. Al-Dulaimi himself has been accused by senior Shiite and Kurdish politicians of inciting sectarian strife.
The Sunni Arab bloc last week suspended its Cabinet membership and said it would quit Wednesday if al-Maliki did not meet its demands: to disband militias, pardon security detainees not charged with specific crimes and include all coalition partners in security decisions.
"The government has not contacted us up until this moment, and it appears that it will not respond," al-Dulaimi said.
In addition to its six Cabinet ministers, the Accordance Front holds 44 of the Iraqi parliament's 275 seats. But al-Dulaimi said Wednesday that his lawmakers would stay in the legislature.
"Withdrawing from the government doesn't mean that we will abandon the whole political process. We will continue our participation...through the parliament and we will contact other parliamentary blocs to achieve our demands," he said.
The Accordance Front scheduled a news conference for later Wednesday.
In other developments: