A missile-loaded Turkish Air Force warplane rises in the sky after taking off from Incirlik Air Base, in Adana, southern Turkey July 29, 2015. (Emrah Gurel/AP)

The Turkish commandos came at dawn, surrounding this town on the Syrian border and hauling nine men off to jail.

It was July 24, just hours after Turkey announced a crackdown on the Islamic State in a major strategic shift for the nation. But the detained men had nothing to do with the militant group. Instead, they were suspected of links to the Kurdistan Workers’ Party, or PKK. That group has fought a decades-long war for autonomy for Turkey’s ethnic Kurdish minority.

As Turkey vowed last month to strike the Islamic State, it simultaneously opened a new front in its conflict with Kurdish rebels. It has launched scores of strikes on PKK strongholds across the border in northern Iraq and detained hundreds at home. The PKK, a Marxist-inspired group that the United States has deemed a terrorist organization, has also stepped up attacks, killing more than two dozen people in Turkey in recent weeks.

Turkish officials have said that both campaigns are part of the same fight against terrorism. But the fresh violence has also rekindled a dispute over Kurdish self-rule that threatens to destabilize Turkey and set off a wider conflict in a region already roiled by war.

“Here, it is a crime to be Kurdish now,” said Jalal Ipek, a resident of Suruc whose 20-year-old son was arrested in the July 24 raids. Police eventually detained a total of 18 men from the Kurdish-majority town, residents and a local defense lawyer said.

“My son was sleeping, and they came to my house with guns,” Ipek said. “I asked them: ‘What is my son’s crime?’ They told me: ‘Don’t speak.’ ” The son, Abdelkader, remains in detention in the nearby city of Sanliurfa.

Last month, Turkey and the United States reached a landmark agreement to allow the U.S. military access to Turkey’s Incirlik air base for strikes on the Islamic State. The United States and allied nations have spent the past year bombing the group in Syria and Iraq.

But critics say Turkey has used the deal as cover for targeting Kurds.

“It is being utilized by the Turkish government in a way that serves them politically,” said Yezid Sayigh, senior associate at the Carnegie Middle East Center in Beirut. “Specifically, it’s allowing them to raise the pressure on the PKK.”

There are several Kurdish rebel groups in Turkey, but the PKK — which is active in both Turkey and Iraq — is the country’s most militant.

The more than 14­ million Kurds in Turkey are part of a wider Kurdish population that lives in Syria, Iraq and Iran. The countries have all sought to repress the Kurds, who maintain a distinct language and culture but have no state of their own. In Turkey, which has a total population of more than 75 million, the government banned Kurds for years from speaking their own language in public. Authorities were worried that the large Kurdish minority would threaten Turkish identity.

But the government recently relaxed those restrictions. And in 2013, Turkey and the PKK reached what many thought was a historic agreement to halt the fighting and grant Kurds more rights.

Amid the tumult in the region, however, the accord soon fell apart. The Turkish government’s resistance to playing a bigger role in the U.S.-led coalition’s campaign against the Islamic State was an especially sore point among the Kurdish minority. Only recent events, including advances by the Islamic State along the border and signs that it is gaining a stronger foothold inside Turkey, appear to have prompted the government to act against the group.

Analysts say Turkey has long viewed the Islamic State as a bulwark against Syria’s Kurdish militias, which have made major territorial gains in that country’s north in recent months. The Kurdish People’s Protection Units, or YPG, have used U.S. air cover to rout the Islamic State from key areas in Syria. That has spooked Turkish officials, who fear that the advances could lay the foundation for a future Kurdish state. The Kurdish militias in Syria are linked to the PKK.

So when a suicide bomber killed more than 32 people at a cultural center in Suruc last month, the PKK leadership accused the Turkish government of negligence. Its fighters resumed attacks on Turkish forces.

“There is no difference between PKK and Daesh,” Turkish Foreign Minister Mevlut Cavusoglu said at a news conference last month, using the Arabic acronym for the Islamic State. The group is “taking advantage of the situation in the region” to undermine Turkey, Cavusoglu said.

But Turkey’s decision to move against the Kurds is likely to do more to destabilize the region, some analysts say.

The police dragnet has fostered resentment against authorities in places such as Suruc, where Kurdish families have relatives living on both sides of the border. The United States has looked the other way as Turkey has hit the PKK in Iraq. The U.S. silence on the Turkish operations may hurt its burgeoning alliance with the YPG, whose fighters have proved to be the most effective ground force battling the Islamic State.

“It’s not smart for Turkey to do this,” Aaron Stein, a nonresident fellow at the Atlantic Council’s Rafik Hariri Center for the Middle East, said of Turkey’s twin military campaigns.

“Opening a two-front air war against insurgents you can’t defeat by air power alone is not smart strategically,” he said. Indeed, the U.S. military says it has launched more than 5,600 strikes on the Islamic State since last August, but the raids have not dislodged the group from its major strongholds.

In Suruc, residents say they expect more arrests. The brother of one of the 18 detainees denies accusations that his sibling, 21-year-old Yunus Kaya, is a leftist militant.

“He is in jail, and we don’t know what he is accused of,” said the brother, who spoke on the condition of anonymity because of the government crackdown.

Lawyer Eman Baran is representing the 18 detainees from Suruc in court. He said police do not have enough evidence to charge his clients. The Turkish prime minister’s office did not respond to requests for comment.

“I don’t believe there is law or justice in Turkey anymore,” Kaya’s brother said. “I just want my brother to come back home.”

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