Iraqi officials say as many as a dozen explosions have hit the capital, Baghdad, killing at least 57 people and wounding nearly 180 others as a political crisis continues in the country.
The apparent coordinated blasts Thursday struck across the city, mainly in Shi'ite areas, days after the final withdrawal of U.S. troops from Iraq.
The attacks come as Iraq's Shi'ite-led government pursues the arrest of Vice President Tariq al-Hashemi on charges that he plotted to kill other government officials.
But Hashemi said Wednesday the allegations are politically motivated by the prime minister, whom Hashemi says wanted to consolidate power when U.S. troops left this month.
Hashemi says that Prime Minister Nouri al-Maliki controls the security and intelligence forces and does not allow other elected officials to interfere. The vice president fled to the semiautonomous Kurdish region of northern Iraq to escape a warrant for his arrest issued this week.
Hashemi, a Sunni, says the United States failed to leave behind a democratic model in Iraq, leaving the nation vulnerable to interference from its Iranian neighbors.
Earlier Wednesday, Prime Minister Maliki, at a Baghdad news conference, called on Kurdish authorities to hand over the vice president.
A spokesman for Iraq's Interior Ministry says three of Hashemi's bodyguards confessed they planted bombs targeting Iraqi government and security officials with Hashemi's backing.
The alleged plot and a call last week by Maliki for a no-confidence vote in parliament against another leading Sunni politician, Deputy Prime Minister Saleh al-Mutlaq, have heightened political tension in Iraq.
On Tuesday, U.S. Vice President Joe Biden urged Iraqi leaders to settle their political differences.
The White House said Biden telephoned Maliki and the speaker of the Council of Representatives, Osama al-Nujaifi. It said Biden stressed the urgent need for the prime minister and the leaders of other political blocs to meet and work through their differences.
Both Hashemi and Mutlaq are leaders of Iraq's mostly Sunni Iraqiya political bloc, part of the coalition government. Iraqiya's members walked out of parliament on Saturday, accusing Maliki of seizing power.