Gulen, who is the spiritual leader of a worldwide movement that includes schools, clinics and charities, has denied involvement in the plot.
He was once an ally of Turkish President Recep Tayyip Erdogan, but the two eventually became rivals. The night of the coup attempt in July 2016, a rogue faction of Turkey’s military hijacked fighter jets, tanks and helicopters in a coordinated attack on the Erdogan government.
But the government thwarted the coup attempt and launched a sweeping crackdown on alleged members of Gulen’s movement, including in other countries.
Earlier this year, Deputy Prime Minister Bekir Bozdag said Turkish intelligence agents carried out operations in 18 countries to pursue coup suspects with alleged links to Gulen.
The Turkish government has also waged a campaign to shutter Gulen-funded schools everywhere from Sudan to Pakistan to the United States.
In recent weeks, Turkish officials have stepped up pressure on the Trump administration to extradite Gulen, whose arrest they first demanded in 2016.
Trump told Erdogan in November his administration “would take a look” at Turkey’s extradition request, White House press secretary Sarah Sanders said.
Trump did not commit to fulfilling the request, she said last month.
U.S. officials have previously said Turkey did not provide sufficient evidence for the U.S. Justice Department to apprehend Gulen.