At least 16 policemen and soldiers were killed in two separate attacks by ISIS militants in northern Iraq on Sunday, security officials said.
Most of the deaths came in an attack on a police checkpoint outside Kirkuk. The authorities did not give details about casualties, but medical and security officials in the city told The National on condition of anonymity that at least 13 policemen were killed and five wounded.
The clashes, which lasted for two hours, took place in the Al Rashad area south-west of Kirkuk, federal police said. Three police vehicles were destroyed.
ISIS militants also attacked an army checkpoint in Makhmour, south-east of Mosul, killing three soldiers and wounding at least one, a police officer said.
The attacks raise questions about the ability of Iraqi forces to maintain security beyond the planned withdrawal of US troops from Iraq by the end of this year. The US has 2,500 troops among the 3,500 members of the international anti-ISIS coalition in Iraq.
The United States has reduced its forces from around 5,000 that were stationed to help combat Islamic State to half that number in the last year.
ISIS controlled about one third of Iraq and Syria from mid-2014 until late 2017.
Nearly four years later after the group's defeat, ISIS fighters are still able to carry out attacks, albeit in remote areas of Iraq, posing a challenge to security forces.
The attack outside Kirkuk was among the deadliest by ISIS this year.
In January, two suicide bombers killed at least 32 people and wounded 110 in a busy commercial area near Baghdad's Tayaran Square.
Six months later, a suicide bomber blew himself up in a crowded outdoor market in Baghdad's eastern district of Sadr City, killing at least 30 and wounding dozens others.
In May, a senior Kurdish official, Lahur Talabany, told Reuters that there are growing indications that ISIS is trying to make a comeback after an uptick in attacks in Iraq.