BAGHDAD (AP) -- A car bomb exploded as Sunni worshippers were leaving a mosque after evening prayers Tuesday in Baghdad, the deadliest in a string of attacks that killed at least 20 people nationwide in a week of the most sustained sectarian violence in the country since U.S. troops withdrew more than a year ago.
Rising tensions between Sunnis and the Shiite-led government have burst into a new round of bloodshed with 279 people killed since last week and scenes reminiscent of some of the worst carnage during the days when the two Islamic sects battled each other as well as U.S.-led forces in the chaotic years after Saddam Hussein's ouster.
The violence has raised fears the country is sliding back to the brink of civil war amid rising Sunni anger over perceived mistreatment at the hands of Prime Minister Nouri al-Maliki's government and dangerous spillover from Syria's civil war next door, which pits mainly Sunni rebels against Syrian President Bashar Assad, a member of the Alawite sect, an offshoot of Shiite Islam.
White House press secretary Jay Carney told reporters in Washington that the U.S. administration was "deeply concerned by the frequency and the nature of recent attacks." U.S. officials in Baghdad and Washington were in contact with a wide range of senior Iraqi leaders "to urge calm and help resolve ongoing political and sectarian tensions," he said Monday.
The explosion targeting the worshippers occurred in the western neighborhood of Abu Ghraib, the site of the infamous prison of the same name, killing 10 people and wounding 21, according to police and hospital officials. A bomb also targeted a tea house in Baghdad's mainly Sunni southern Dora neighborhood, killing three people and wounding 14, two police officers and a medical official said.
Several smaller attacks struck areas elsewhere in the country earlier Tuesday.
A suicide bomber set off his explosives-laden vest at a military checkpoint in the town of Tarmiyah, 50 kilometers (30 miles) north of Baghdad. The blast was followed by militants who opened fire at the Iraqi troops, killing three soldiers and wounding nine, a police official said.
In the northern city of Tuz Khormato, two parked car bombs went off simultaneously, killing three civilians and wounding 38 people, said Mayor Shalal Abdool. The town is about 200 kilometers (130 miles) north of the Iraqi capital.
And in Kirkuk, 290 kilometers (180 miles) north of Baghdad, three bombs exploded back-to-back at a sheep market, killing one person and wounding 25, police Col. Taha Salaheddin said.
Authorities also raised the death toll from Monday's wave of bloodshed -- a series of blitz attacks stretching from north of Baghdad to the southern city of Basra and targeting bus stops, open-air markets and rush-hour crowds -- to 113 after many of the wounded died of their injuries. That made it the deadliest single day since July 23, 2012, when attacks aimed largely at security forces killed 115.
No one has claimed responsibility for the attacks, but such systematic carnage carries the hallmarks of the two sides that brought nearly nonstop chaos to Iraq for years: Sunni insurgents, including al-Qaida's branch in Iraq, and Shiite militias defending their newfound power after Saddam's fall.
Hours after Monday's stunning bombings, al-Maliki accused militant groups of trying to exploit Iraq's political instability and vowed to resist attempts to "bring back the atmosphere of the sectarian war."
Under Saddam, Iraq's Sunni minority held a privileged position, while the Shiites were largely oppressed. But since the 2003 U.S.-led invasion that toppled Saddam, those dynamics have been flipped.
Many Sunnis contend that much of the country's current turmoil is rooted in the policies of al-Maliki's government, which they accuse of feeding sectarian tension by becoming more aggressive toward the minority community after the U.S. military withdrawal in December 2011.
Protests by Sunnis, which began in December amid anger over alleged random detentions and neglect, have largely been peaceful. However, the number of attacks rose sharply after a deadly security crackdown on a Sunni protest camp in northern Iraq on April 23.
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