The tensions raised by the Salahuddin officials’ actions cut to the heart of sectarian grievances across the whole country, where tens of thousands of Sunni families have been displaced either by the Islamic State or by government offensives against the group. Even as Mr. Abadi’s national government has tried to address reports of abuses by the Shiite-dominated security forces and their militia allies, deep distrust persists in Iraq’s Sunni communities.

In an interview, Mishan al-Jiboori, a member of Parliament from Salahuddin Province, accused the provincial security commander of human rights violations against “the innocent and the repressed.”

The Salahuddin operations commander, Brig. Gen. Juma Enad Sadoon, called critics like Mr. Jiboori “barking dogs and mercenaries” and said they should not interfere in security matters in Tikrit. In an interview, General Sadoon did not indicate whether the removals would be halted.

The evictions have evoked unwelcome comparisons to collective punishments, including home demolitions, imposed by Israel against families of Palestinians accused of attacks. Collective punishment is prohibited under the Third and Fourth Geneva Conventions and is generally considered illegal under international law.

Officials in Tikrit cited extraordinary security concerns for the evictions.

“This is a very difficult situation for us because of the terrible suffering caused by Daesh,” Mr. Hekmat said. “We are under great pressure to rebuild our city and impose civil order” after almost a year under Islamic State occupation in 2014 and 2015, he said.

Khazhal Hamad, the province’s first deputy governor, said the removals protected families from retaliation by neighbors who lost family members to ISIS attacks. “There are hostile feelings toward these people, and these feelings can affect the civil peace we are trying to achieve,” Mr. Hamad said.

The Tikrit evictions are perhaps a prelude to postcombat frictions in the city of Mosul, 140 miles north, if government forces can uproot Islamic State forces there.