BAGHDAD -- At least 70 people were killed and about 100 wounded by explosions in Iraq's capital on Wednesday.

A fuel tanker exploded near a gas station in western Baghdad,, killing at least 50 people and wounding 60, police said. Police said it was the work of a suicide attacker.

A parked car bomb left a gaping crater in a busy square in central Baghdad. Three minibuses and six cars were damaged by flames and flying debris. Karradah had previously been thought to be one of central Baghdad's safest areas.

The bombing occurred nearly a week after a cluster of explosions, including one from a massive truck bomb, hit the same neighborhood.

Iraqi police also say a parked car bomb killed three people and wounded five in southern Baghdad.

Deadliest July For U.S. Troops

The Pentagon announced the deaths of three more U.S. soldiers on Wednesday, after a what the military called a sophisticated, armor-piercing bomb exploded near their patrol in eastern Baghdad. Six other soldiers were wounded.

Another soldier was killed by small arms fire Tuesday in a separate incident, the military said. All of the victims' names were withheld pending family notification.

Seventy-six U.S. troops died in Iraq during July, the Pentagon said Wednesday. It was the lowest monthly count in eight months, but the deadliest July for U.S. troops since the war began.

By the military's official count, 3,647 U.S. troops have died in Iraq since the invasion. Of those, 2,998 were killed on action. More than 26,000 U.S. troops have been wounded, of which more than 12,000 have not returned to the battlefield.

For full casualty report, click here.

Sunni Bloc Withdraws

Iraq's largest Sunni Arab political bloc said Wednesday ot planned to withdraw from the government, threatening Prime Minister Nouri al-Maliki's efforts to seek reconciliation among the country's rival factions.

Rafaa al-Issawi, a leading member of the Accordance Front, which has 44 of parliament's 275 seats, said the bloc's six Cabinet ministers would submit their resignations later in the day.

The decision to pull out from the government followed what al-Issawi called al-Maliki's failure to respond to a set of recent demands. Among them: a pardon for security detainees not charged with specific crimes, the disbanding of militias and the participation of all groups represented in the government in dealing with security issues.

"The government is continuing with its arrogance, refusing to change its stand and has slammed shut the door to any meaningful reforms necessary for saving Iraq," al-Issawi said.

"We had hoped that the government would respond to these demands or at least acknowledge the failure of its policies, which led Iraq to a level of misery it had not seen in modern history. But its stand did not surprise us at all," he said.