A wave of explosions rattled the Iraqi capital after sunset on Monday, killing at least 30 people as al Qaeda claimed responsibility for a spate of rare suicide attacks last month in the northern, relatively peaceful self-ruled Kurdish region.
Attacks on anti-Qaeda fighters earlier in the day claimed another five lives.
The attacks are the latest in a surge of bloodshed that has roiled Iraq for months, heightening worries that the country is returning to the widespread sectarian killing that marked the years following the 2003 U.S.-led invasion.
Police reported casualties from explosions in eight different neighborhoods.
The force of one powerful blast, a car bomb explosion in the Bab al-Sharji neighborhood that killed three and wounded 11, rattled windows in central Baghdad.
The deadliest attack happened when a car bomb and roadside bomb exploded in a market and nearby parking lot in the northern Shiite district of Husseiniya, killing six and wounding 13.
Car bombs also hit the mainly Shiite neighborhoods of Zafaraniyah, with four killed and 11 wounded, Alam, with two dead and 10 wounded, Obeidi, with two killed and eight wounded.
Confessionally mixed neighborhoods were also hit. A roadside bomb hit a commercial street in Kam Sarah, killing three and wounding eight, and the eastern Baghdad al-Jadidah, killing three and wounding 17.
Another car bomb exploded in shopping streets in the mainly Sunni neighborhood of Dora, killing four and wounding eight, and in the mostly Sunni area of Sadiyah, killing three and wounding 10.
Hospital officials confirmed the casualties. The authorities spoke on condition of anonymity because they weren't authorized to brief reporters.
There was no immediate claim of responsibility, but coordinated bomb blasts in civilian areas are a frequent tactic by al Qaeda's Iraq arm.
Earlier, al Qaeda claimed responsibility for a spate of rare suicide attacks last month in the northern, relatively peaceful self-ruled Kurdish region, underlining the terror group's growing strength across the country.
The Sept. 29 twin suicide car bombs hit a complex housing the regional Interior Ministry and other security agencies in Irbil, the capital of the Kurdish region, killing at least six Kurdish troops and wounding more than 30 others.
The attacks were the biggest since 2007, when a suicide truck bombing hit the same ministry, killing 14 people, and 2004, when a twin suicide attack killed 109.
In a statement posted Monday on a militant website, the Islamic State of Iraq and the Levant said the attacks were in retaliation for statements recently made by the regional President Massoud Barzani expressing readiness to help the Shiite-led central government in Baghdad in its fight against insurgents, and also offering to assist Kurdish militias in neighboring Syria. al Qaeda-linked militants in Syria have been fighting ethnic Kurds in Syria's northeast.
Since 2003 U.S.-led invasion, the Kurdish region in northern Iraq has been relatively peaceful compared to the rest of the country, making it the best destination for foreign investors across sectors.
The authenticity of the statement by al Qaeda's Iraq branch could not be independently verified but it was consistent with the group's earlier statements.
The Irbil attacks were the latest in a bout of violence that began in April, the deadliest turmoil since 2008. Most of the attacks, which have killed more than 5,000 people since April, have been claimed by al Qaeda.
Earlier on Monday, bombs targeting patrols of pro-government, anti-al Qaeda Sunni militia members outside Baghdad, killing five and wounding 10, two police officers and two medical officials said on condition of anonymity as they were not authorized to release information.
The Sunni militiamen, or Sahwa, joined with US troops to fight al Qaeda during the height of an insurgency. Since then, they have been a frequent target for al Qaeda in Iraq, which considers them traitors.
Also Monday, Iraq's parliament said in a statement that lawmakers set April 30 as the date for holding national elections. Iraq's last national elections were held in March 2010. It took political rivals nine months to form a government. Since then, the Defense and Interior portfolios have been held by embattled Prime Minister, Nouri al-Maliki, because of ongoing political wrangling.