Eighteen Iraqis, the majority military personnel, were killed overnight Friday to Saturday in separate jihadist attacks mainly in the greater Baghdad area, security sources told AFP.
There was no immediate claim of responsibility for the attacks, but they are in line with the modus operandi of the Islamic State group, which still has sleeper cells in Iraq despite its territorial defeat in 2017.
One attack targeted troops in Tarmiya, an agricultural suburb 20 kilometers (12 miles) north of the Iraqi capital.
"IS fighters attacked an Iraqi army convoy at night and killed two officers and two soldiers," a security official said, on condition of anonymity.
Reinforcements were dispatched to the area but also came under fire, with "an officer and two soldiers" killed, the source said.
A member of tribal fighters integrated into the regular forces that were then deployed to the scene was also killed, "along with a civilian caught in the crossfire", the source added.
Further north, in the central Alton Kubre region, "six peshmerga (Kurdish fighters) were killed when Islamic State group jihadists attacked their military position with light arms", another security official told AFP.
Alton Kubre is a disputed area claimed by both the federal government in Baghdad and the autonomous Kurdistan authorities.
Another attack took place in the western desert bordering Syria, a third security source said.
"An officer and a soldier were killed in a bomb explosion while an army convoy was en route to Akashat," he said.
A soldier was also killed in a bomb blast in Diyala province, which borders Baghdad to the east, according to another official, who added that two other fighters were also wounded in a separate attack.
Iraq in late 2017 declared victory over IS, which had overrun swathes of the country and neighbouring Syria three years earlier.
However, sleeper cells holed up in mountains and deserts continue to carry out deadly attacks across the country, often at night in remote areas and with light weapons.
Following the latest attacks, Iraqi President Barham Saleh called in a tweet for continued "effective international support to eradicate terror across the region".
A US-led military coalition has been in Iraq since 2014 to help fight IS but a vote in parliament last year called for the departure of all foreign troops from the country.