Mr. Musa, 60, now shares a blue-and-white tent with nine family members whose only crime was to have a relative who had joined the Islamic State, also known as ISIS, ISIL or Daesh.
Several women evicted from their homes and trucked to the Shahama camp said Iraqi security forces demolished their houses with explosives after accusing their sons or husbands of joining the terrorist group.
The authorities of Salahuddin Province say the punishment against the families of ISIS members is intended to force the group’s recruits to pay a painful personal price.
“Our aim is to defy the terrorists and send a stern message to the families,” Amar Hekmat, the deputy governor, said inside the barricaded provincial government center.
But the evictions have set off a rancorous dispute between officials in Tikrit and politicians in Baghdad. Prime Minister Haider al-Abadi, in a letter to the provincial governor last week, sharply criticized the removals and ordered provincial and Baghdad officials to resolve the issue.
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.
Tikrit is a potent symbol of Sunni dominion in central Iraq. Saddam Hussein was born in Awja, just outside Tikrit, and his palaces still tower over the landscape here. Yet Shiite Muslim militias, backed by Iran and known as popular mobilization forces, led the charge to evict the Islamic State from the city in April 2015.
The main highway into Tikrit is now festooned with posters featuring the faces of Shiite militiamen killed in battle and images of the revered Shiite imams Hussein and Ali. Some of the posters are mounted next to Iraqi government military compounds.
But local Sunni militiamen, along with Iraqi security forces, have themselves carried out some of the evictions — all targeting Sunnis. Thousands of Sunni tribal fighters had joined the fight against ISIS in Tikrit.
Today, pockets of Islamic State fighters remain in Tikrit districts west of the Tigris River. Security officials said the small militant cells occasionally fired mortars from Sunni neighborhoods where many of the evictions have occurred.
Hussein Ahmed Khalaf, director of the Shahama camp, said none of the 345 evicted families — 1,111 people — had been permitted to return home. All will undergo security screenings to determine their fates, he said.
Several of those evicted said security forces had confiscated their cellphones and interrogated them about family members’ ties to the Islamic State. They said they had not been told when, or whether, they would be allowed to return home.
Several acknowledged that fathers or sons had joined ISIS, but they insisted that they supported the Iraqi government. They said their children had been removed from school and compelled to endure a harsh existence in the forlorn Shahama camp.
“What is the guilt of my children? They don’t know anything about Daesh,” said Eman Khalil Hamad, 34. She said she and her seven children had been evicted and their five-room home demolished to punish her husband, an Islamic State fighter she said she had not seen for months.
Ms. Hamad said the family had suffered under the Islamic State’s harsh social codes. But now, she said, she was abused by security forces who slapped and insulted her as she was forced onto a military truck this month.
Hussein al-Gibory, 55, a Sunni Muslim tribal sheikh and a commander of a Sunni militia force that helped restore Tikrit to government control, said collective punishment was counterproductive.
“It will only turn people away from the government and strengthen Daesh,” said Mr. Gibory, who wore combat fatigues with military insignia of the popular mobilization forces — the collective name for militia forces in Iraq.
He said authorities should use “social rehabilitation” to convince families of Islamic State members that “Daesh is more dangerous than a nuclear bomb.”
“We are tribal people,” Mr. Gibory said. “We should turn to dialogue rather than dragging women and children from their homes.”
Mr. Musa, the father of the ISIS fighter, said he felt betrayed by his government. He said he had alerted the tribal sheikh in his village, on Tikrit’s west side, after his son joined the group, and disavowed both his son and the Islamic State.
The sheikh signed and stamped a letter attesting to Mr. Musa’s innocence. But the security forces who evicted him refused to read the document, Mr. Musa said, clutching the worn letter inside his camp tent.
Hadia Ibrahim, 44, a mother of 11 children, said two of her sons — one an Iraqi police officer — had been killed by the Islamic State. But she said she and her four daughters were now confined to the Shahama camp after her husband joined ISIS in 2014, she said.
When security forces descended on her home three weeks ago, Ms. Ibrahim said, they told her, “You are the family of Daesh — leave!”
Mr. Hamad, the first deputy governor, said evicted families ultimately might be moved to other areas, or even other provinces. “That is to be determined by security agencies,” he said.
Some families with Islamic State relatives have fled Salahuddin Province altogether to avoid evictions, Mr. Hamad said.
“Those people,” he said, “will never be allowed to come back.”