A group of pro-government lawyers in Turkey have filed charges against several U.S. officers associated with Incirlik Air Base, seeking their arrest for alleged ties to terrorist groups.

The accusations come amid increased tensions between the U.S. and Turkey, a NATO ally that has cracked down in recent years on political opposition, shut down media outlets and tightened control of the court system, according to international aid groups.

The lawyers are seeking a temporarily halt to all flights leaving the base and access to execute a search warrant, according to court papers filed last week by the Association for Social Justice and Aid. The group is a well-known, non-governmental organization made up of backers of Turkish President Recep Tayyip Erdogan.

The Stockholm Center for Freedom, a group of exiled journalists from Turkey, said that the warrants were likely filed in response to the U.S. levying economic sanctions on Interior Minister Suleyman Soylu and Justice Minister Abdulhamit Gul for their roles in the detention of American pastor Andrew Brunson.

Brunson has been held in prison since October 2016 on charges of belonging to a terrorist organization, allegations that the U.S. government and international human rights organizations refute.

The U.S. imposed the sanctions after Turkey refused to free Brunson, who was last week moved from prison to house arrest in İzmir for pretrial detention.

Erdogan has publicly linked the release of Brunson to a request for the U.S. to deport Muhammed Fethullah Gulen, a Muslim religious leader living in Pennsylvania that the Turkish government says is responsible for the July 15, 2016 coup attempt in Turkey.

The court papers accuse the American officers and NCOs cited of having connections to the FETO group allegedly run by Gulen and trying to “destroy the constitutional order” of Turkey.

The 60-page criminal complaint seeks the arrest of Col. John C. Walker, Col. Michael H. Manion, Col. David Eaglen, Col. David Trucksa, Lt. Col. Timothy J. Cook, Lt. Col. Mack R. Coker, and Sgts. Thomas S. Cooper and Vegas M. Clark.

Gen. Joseph Votel, the commander of the U.S. Central Command, retired U.S. Army Gen. John F. Campbell and Air Force Brig. Gen. Rick Boutwell, director of regional affairs for the deputy under secretary of the Air Force, were also named in the complaint.

The Air Force said it is aware of the reports but referred all questions to the Turkish government for comment.

“We continue to carry out our mission here at Incirlik Air Base, and we are proud of the relationship we have with our Turkish military partners,” said Air Force Capt. Amanda Herman, spokeswoman for the base.