Several violent attacks ripped through Iraq, killing at least 110 people and wounding more than 200 in the deadliest day of attacks this year.
Insurgents carried out the coordinated attack in at least 15 cities Monday. It was Iraq's bloodiest day since May 10, 2010 when more than 100 people were killed.
The shootings and bombings follow a warning last week by the head of the al-Qaida group in Iraq that he was stepping up operations in areas vacated by U.S. troops last year.
Jihadist websites posted a message Saturday, reportedly from the leader of al-Qaida's affiliate in Iraq, saying the group is starting a "new phase." The audio message from a speaker identified as Abu Bakr al-Baghdadi says his group is planning to attack court officials, and to free prisoners.
In June, the group claimed responsibility for a wave of car bombings that killed 72 people and wounded nearly 260 others.
Authorities said the attacks in 12 Iraqi locales targeted government and military installations. They included gunmen killing at least 15 Iraqi soldiers at a military base in the northeastern town of Udaim, as well as a series of explosions in the northern city of Kirkuk.
A car bomb also exploded in Baghdad. The deadliest attacks targeted Taji, just north of the capital, where bombs planted in five houses killed at least 40 people and wounded scores more.
There was no immediate claim of responsibility, but the attacks appear well-coordinated. Coming during the holy time of Ramadan, they again call into question the ability of the fractured Iraqi government to halt terror.
"It was a thunderous explosion," said Mohammed Munim, 35, who was working at an interior ministry office that issues government ID cards. That attack killed 16.
"The only thing I remember was the smoke and fire, which was everywhere," Munim said from from a Sadr City hospital where he was recovering from shrapnel wounds.
Violence in Iraq has increased in recent weeks, with attacks in June killing at least 237 people and leaving many Iraqis wondering if their government is able to guarantee security since the departure of U.S. troops.
In early July, bombings across Iraq killed at least 40 people and wounded nearly 100 others. In January, several bombings targeting Shi'ites killed 78 people.