The explosions capped a week in which about 100 people were killed in bombings and shootings nationwide, including at least 26 who died in a commando-style assault against the central bank in Baghdad last Sunday. An al-Qaida in Iraq front group, the Islamic State of Iraq, claimed responsibility for that attack, saying it targeted the institution responsible for funneling "oil money and the stolen wealth of Muslims" to the West.

An Iraqi soldier is seen at blast site in Baghdad, capital of Iraq, June 20, 2010. At least 33 people were killed and 54 were wounded in two car bomb explosions in western Baghdad on Sunday. [Xinhua]

Sectarian bloodshed that pushed the country to the brink of civil war in 2006-2007 has dropped sharply after a series of U.S.-Iraqi offensives, a Sunni revolt against al-Qaida and a Shiite militia cease-fire. But Iraqis still face near-daily attacks.

Many are venting their anger at politicians for failing to choose a prime minister and form a government, even though the new parliament was seated last week. Prime Minister Nouri al-Maliki has been acting in a caretaker role as he battles to keep his job after a rival Sunni-backed political bloc won a narrow victory in the March 7 parliamentary vote.

The head of the Iraqiya bloc, Ayad Allawi, has warned more violence could ensue if the Sunnis who backed him feel sidelined by a Shiite alliance between al-Maliki's party and a hard-line religious group.

Ahmed Abdullah, an engineer in the Electricity Ministry, said bickering politicians "have encouraged al-Qaida sleeper cells to resume work and strike again."

"Ordinary Iraqis are paying the price of the political struggle in Baghdad," he said.

Hassan al-Janabi, a 44-year-old hotel employee in Baghdad, said he has altered his routine to avoid crowded areas and rush hour traffic, which have been popular targets for insurgents seeking to maximize casualties.

"I believe the deteriorating security situation is connected to the political struggle and the fight between politicians over power and government," he said. "I think that attacks will increase because regional countries will increase their interference in Iraq after the upcoming withdrawal of US forces."

The ability of insurgents to penetrate areas with tight security has raised questions about the readiness of Iraqi forces to take over their own security less than three months before all American combat troops are to leave the country, the first step toward a full withdrawal by the end of next year.