Suicide bombers have targeted two major cities in Iraq, striking security forces in the Sunni city of Fallujah and Shi'Ite pilgrims in the holy city of Karbala in the country's south, killing at least six people in each attack.
The bombings are an apparent attempt by the Islamic State group to strike back as government troops' advance on their stronghold in the northern city of Mosul.
In Fallujah, the attack was carried out by twin suicide car bombers in the city centre - the first such incidents since Iraqi forces in late June declared it "fully liberated" of Islamic State militants after a monthlong operation aided by US-led airstrikes.
Interior Ministry spokesman Brigadier General Saad Maan said one of the Fallujah bombers killed two policemen and wounded 17 people, including nine civilians.
"They hit a security checkpoint," he said, adding that traffic had been heavy in the area and around 10 vehicles including an ambulance had been damaged. The second bomber killed four people, including two policemen.
IS claimed responsibility for the attack, posting videos online of the bombers before the bombings, their faces masked and brandishing assault rifles.
Earlier in the day, a suicide bombing targeted the sacred Shi'Ite city of Karbala, killing at least six civilians in an attack also claimed by IS.
According to Maan, the ministry spokesman, six suicide bombers tried to sneak into Karbala from its western outskirts but security forces detected and killed five of them.
The sixth attacker broke into a house in the city's Ayn al-Tamer neighbourhood, where he detonated his suicide vest, killing six people and wounding another six.
The attack came as hundreds of thousands of faithful Shi'Ites have been walking to Karbala to commemorate the 7th century death of Imam Hussein, Prophet Muhammad's grandson and an iconic Shi'Ite martyr.
In an online statement, the Islamic State group said it targeted "polytheists ... in filthy Karbala."
It put the number of the suicide bombers at five, saying they clashed for hours with the security forces and set off their explosives consecutively when they ran out ammunition.
The militants often exaggerate their claims. The Associated Press could not verify the authenticity of the statement, but it was posted on a militant website commonly used by the extremist group.
Like other Sunni extremist groups, IS considers the Shi'Ites heretics and has frequently targeted Shi'Ite civilians and places of worship.
