A Turkish national flag is seen on Eyup Sultan mosque on July 26 in Istanbul after the failed military coup of July 15. (Ozan Kose/AFP via Getty Images)

ISTANBUL — Barely a day after the Pentagon's top official arrived in Turkey in a bid to cool growing tensions between Ankara and Washington, a Turkish lawyer filed a criminal complaint against him and two other senior U.S. officials.

It accused Marine Gen. Joseph F. Dunford Jr., the chairman of the Joint Chiefs of Staff; Gen. Joseph Votel, the top U.S. commander in the Middle East; and Director of National Intelligence James R. Clapper Jr. of conspiring with the plotters behind the July 15 coup attempt, which ended only after a rebellious faction of the military had bombed parliament and turned their weapons on civilian protesters in Istanbul and Ankara.

Local media reports identify the lawyer as Mert Yilmaz and say that part of the evidence he presents against the U.S. officials includes the White House's supposedly delayed condemnation of the coup plot as well as the presence of pro-coup commentary on American TV outlets such as Fox News.

Although it's unclear whether prosecutors in Ankara will take on the case, it's a sign of the heated atmospherics surrounding U.S.-Turkish relations since last month.

President Recep Tayyip Erdogan and other officials in the Turkish government pin the blame for the coup on Fethullah Gulen, an imam living in self-imposed exile in Pennsylvania who presides over a vast network of schools, charities and businesses around the world. Gulen's critics say his supporters — dubbed "Gulenists" — have infiltrated various institutions, including the military, and were simply biding their time to strike.

Turkey is in the grip of an unprecedented purge of its government and society, in which tens of thousands of troops, lawyers, journalists, academics and others with alleged links to Gulen's organization have been arrested, detained or suspended from their jobs. Human Rights Watch has deemed the scale of the crackdown "an affront to democracy."

"I hereby declare that anyone who continues to adhere to the delusions of the charlatan of Pennsylvania from this moment on has accepted the consequences," Erdogan said Wednesday.

Meanwhile, Turkish officials insist on Gulen's extradition from the United States and have submitted legal documents to American authorities. U.S. officials say they are waiting for specific evidence directly linking Gulen to the failed coup.

This irks Ankara, not the least Erdogan, who has publicly accused Western governments of not sufficiently standing behind Turkey's democratically elected government while unfairly lecturing Ankara over the nature of its crackdown.

"We have not received the support we were expecting from our friends, neither during nor after the coup attempt," Erdogan said in a speech Tuesday.

"A coup was staged in a country ruled by democracy and there are 238 martyrs and 2,200 wounded so far. You still say, ‘We are concerned.’ How can you show affection to the perpetrators of such a thing?" he asked.

The ill will toward the United States, in particular, seems to be widespread in Turkey, where many remain bemused over Gulen's continued freedom in his lavish compound in Saylorsburg, Pa. Conspiracy theories abound.

"Where does Gulen live? In the U.S. Who provides him opportunities? The CIA," Ilker Basbug, a former head of the country's military, said this week on Turkish television. "Did this intelligence agency give him a residence permit for nothing? Do you think that the intelligence will not use him?"

During his Monday visit to Ankara, Dunford met with his Turkish counterpart in the military, Prime Minister Binali Yildirim, as well as lawmakers. He told a group of American reporters that the conversations were productive and cordial.

“The tone in all three meetings was very positive and not accusatory at all,” Dunford said.

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