The Islamic State group launched a coordinated assault on a natural gas plant north of Baghdad that killed at least 14 people, while a string of other bomb attacks in or close to the capital killed 15 others, Iraqi officials said.
The attack on the gas plant started at dawn with a suicide car bomber hitting the facility's main gate in the town of Taji, about 20 kilometers (12 miles) north of Baghdad. Then several suicide bombers and militants broke into the plant and clashed with the security forces, an official said, adding that 27 troops were wounded.
The IS-affiliated Aamaq news agency credited a group of "Caliphate soldiers" for the attack.
In a statement, Deputy Oil Minister Hamid Younis said firefighters managed to control and extinguish a fire caused by the explosions. Younis said technicians were examining the damage.
A car bomb targeting a shopping area in the town of Latifiyah, about 20 miles (30 kilometers) south of the capital, killed seven people, including two soldiers, police and hospital officials said. They said that 18 people were also wounded in the attack, four of whom were soldiers.
Elsewhere in Baghdad, three separate bomb attacks targeted commercial areas, killing at least eight civilians and wounding 28 others, police added.
Medical officials confirmed the casualty figures. All officials spoke on condition of anonymity as they were not authorized to release information.
The Sunday attacks killed 29 people across Iraq. Since Wednesday, more than 140 people have been killed in a spate of bombings in Baghdad and elsewhere.
The wave of attacks comes as Iraqi ground forces have achieved a number of key territorial victories against the extremist group.
"This perverse caliphate is shrinking," said the Obama administration's diplomatic point man in the international fight against the Islamic State group. Brett McGurk, a presidential envoy to the 66-member anti-IS coalition, told journalists in Jordan Sunday that the tide is turning against the extremists.
IS extremists still control significant areas in northern and western Iraq, including the second-largest city of Mosul. It has declared an Islamic caliphate on the territory it holds in Iraq and Syria.
The group has recently increased its attacks far from the front lines in a campaign that Iraqi officials say is an attempt to distract from their recent battlefield losses.