More than 40 people were killed and nearly 200 wounded in Iraq after a string of explosions stuck towns and cities across the country on Tuesday.

It was the deadliest day in Iraq in nearly a month. At least 16 car bombs were detonated in a dozen cities in what authorities believe were coordinated attacks. The deadliest incident took place in Kerbala, a holy city in the country's predominantly Shi'ite south, where two simultaneous explosions killed 13 people and wounded nearly 50.

The second explosion caused the biggest destruction. I saw body parts, fingers, hands thrown on the road, 23-year-old shop owner Murtadha Ali Kadhim told Reuters.

The security forces are stupid because they always gather at the site of an explosion and then a second explosion occurs. They become a target.

Tuesday marks the ninth anniversary of the U.S. invasion of Iraq in 2003. Along with Kerbala, there were explosions in Baghdad, Kirkuk, Baiji, Samarra, Tuz Khurmato, Daquq and Dhuluiya in the country's north, Ramadi in the west, and Hilla, Latifiya and Mahmudiya in the south.

The bombs were planted outside a number of civilian and official targets, including schools, a juvenile center, police stations and the Foreign Ministry in Baghdad.

Police also defused bombs in Baquba and Falluja, Reuters reported.

No one has claimed responsibility for the bombings, but military officials blamed al Qaeda insurgents, according to CNN.