BAGHDAD (AP) -- A string of bombings in mostly Shiite-majority cities across Iraq on Sunday killed at least 31 people and wounded dozens, officials said, a grim reminder of the government's failure to stem the uptick in violence that is feeding sectarian tensions in the country.
There was no immediate claim of responsibility for the latest attacks, but car bombs are frequently used by al-Qaida's Iraq branch.
The Sunni militant group and other Sunni extremists often targets Shiite civilians in an effort to undermine the Shiite-led government. Al-Qaida's extremist ideology considers Shiites heretics.
The deadliest of Sunday's attacks, which targeted mainly commercial areas and bus stations, was in the southern city of Hillah, 95 kilometers (60 miles) south of Baghdad. Back-to-back car bombings hit an outdoor market there, killing eight people and wounding 22, a police officer said.
Two parked car bombs ripped through a commercial area in the city of Suwayrah, 40 kilometers (25 miles) south of Baghdad, killing five people and wounding 14. Two other car bombs exploded simultaneously in the city of Kut, 160 kilometers (100 miles) southeast of Baghdad, killed four and wounded 16.
In nearby city of Samawah, 370 kilometers (230 miles) southeast of Baghdad, four other people were killed and 13 wounded when two car bombs exploded. Two other car bombs killed three and wounded 13 in the city of Diwaniyah, 130 kilometers (80 miles) south of the capital.
In the northern city of Samarra, two people were killed and 15 were wounded when a bomb targeted a gathering of mourners for some of the 17 people who were killed in a car bombing there on Saturday. Five other people were killed and 34 were wounded in other attacks in the southern city of Basra and the central towns of Mahmoudiyah and Madain.
Medical officials confirmed the causalities. All officials spoke on condition of anonymity because they were not authorized to talk to the media.
More than 5,000 people have been killed in Iraq since attacks began accelerating in April following a deadly security crackdown against a Sunni protest camp in the northern town of Hawija.
With today's death toll, more than 258 people were killed so far in October. The latest surge in violence has raised fears that Iraq could be returning to widespread sectarian killings similar to those that brought country to the edge of civil war in 2006 and 2007.
Associated Press writers Sameer N. Yacoub and Qassim Abdul-Zahra contributed to this report.
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