Iraq's Salahaddin province declared three days of mourning from Sunday over a deadly attack blamed on ISIS, as some criticized the state for failing to fight back extremists.
Late Saturday, a roadside bomb hit a civilian car on an open road about 200 kilometers north of Baghdad, police and a local official said.
When security forces arrived to the scene, militants opened fire on them.
The attack killed at least six Iraqi security personal and four civilians, including one who died of his wounds overnight, according to local medics.
There was no claim by ISIS but both the mayor and police blamed the group, which Iraq's government said it had defeated in late 2017.
Two weeks ago, 11 people were killed in an ISIS attack on a lookout post at Al-Radwaniyah on Baghdad's outskirts.
The attacks have coincided with a new campaign by Iraq's security forces to arrest militants in hiding across the country -- but some say it has not been enough.
"Iraqi security forces just assured us this area had been cleaned," wrote Mashaan al-Jaboury, an MP representing Salahaddin, on Twitter late Saturday.
For Jamal al-Dhari, writing on Twitter, the latest ambush "sheds light on the repeated failures in the fight against terrorism."
"The government of Mustafa al-Kadhimi must seriously put in placed a national strategy... and stop being satisfied with 'investigative committees,'" said Dhari.