At least 37 killed in spate of deadly Iraq bomb blasts (VIDEO)

The Sunday attacks targeted outdoor markets and commercial streets packed with people at the start of the local workweek. All the blasts took place in Shiite districts, and most involved parked cars loaded with explosives.

A total of eight car bombs and two improvised explosive devices went off on Sunday, police officials said, adding that eleven more roadside bombs were also defused.

The number of those injured in the blasts has risen to more than 130,police and hospital officials said, according to AP.

The attacks were “well planned and well coordinated,” Al Jazeera reported. So far, no one has claimed responsibility for the bombings, but several similar recent attack were attributed to Sunni extremist groups linked to Al-Qaeda. Sunni extremists consider Shia Muslims to be heretics, and close allies of Iran.

Terrorist attacks targeting civilians and security officials have claimed up to 300 lives in Iraq since the start of the year, with three large-scale attacks taking place in February.

On Saturday, Ali Aouni, head of the Iraq Defense Ministry’s intelligence academy, and his two bodyguards were assassinated by a suicide bomber in the north of the country.

The recent rise of violence comes amid frequent anti-government rallies and sit-ins staged by the Sunni community of Iraq, and is believed to be aimed at fueling sectarian tensions and undermining confidence in the ruling coalition. However, those protesting against Prime Minister Nouri Al Maliki and his Shiite-dominated government have distanced themselves from the extremist groups, and have rejected violence.