A wave of attacks on mostly Shi'ite Muslim targets across Iraq has killed at least 55 people and wounded more than 225 others in one of the bloodiest days of violence since U.S. troops pulled out of the country in December.
Video clip: Iraq Violence
The apparently coordinated bombings and shootings took place over hours in the capital, Baghdad - where at least 32 people were reported killed - and in 11 other cities. Ten separate explosions rocked Baghdad's mainly Shi'ite districts during the morning rush hour, while other attacks targeted police patrols, commuters and crowds in shopping areas.
The Interior Ministry blamed the violence on the Islamic State of Iraq, an umbrella organization for al-Qaida-linked Sunni Muslim insurgents in Iraq. But no group claimed responsibility for the attacks.
The blasts hit just weeks before Baghdad plans to host the Arab League's annual summit in late March. Several senior Iraqi officials said Thursday's deadly violence was likely aimed to frighten diplomats from attending the summit.
Last year's planned summit in Baghdad was cancelled because of regional turmoil and acrimony between Iraq's Shi'ite-led government and some Sunni Gulf states.
The Thursday attacks follow a Sunday car bombing in Baghdad that killed at least 19 recruits and officers outside a police academy.
Prior to that, the capital had seen weeks of relative calm accompanied by the easing of political tensions between Iraq's Shi'ite prime minister and senior members of a Sunni political bloc.
In early January, al-Qaida claimed responsibility for an attack that killed 78 people, mostly targeting Shi'ite pilgrims in Baghdad.
Some information for this report was provided by AP, AFP and Reuters.