"The full story of the July 15-16, 2016, Turkish coup attempt may not be known for some time, but it is clear that a limited number of officers attempted to overthrow the government and either capture or kill elected President Recep Tayyip Erdogan. The government has accused these officers of belonging to the Fethullah Gulen movement (Hizmet), which is certainly possible since many of Turkey's most secular military leaders were removed in earlier purges when Erdogan and Gulen were allies. These secular senior officers were often replaced by individuals associated with either the ruling Justice and Development Party (AKP) or the Gulenist movement, which the government did not view as a threat prior to 2013. Since then, Erdogan has viewed Gulen as an enemy, and the clerical leader has remained in voluntary exile in Saylorsburg, Pennsylvania. Erdogan is now seeking Gulen's extradition to Turkey on charges of masterminding the coup, but his government has produced no clear evidence to back up that request."
U.S. Army War College Strategic Studies Institute: http://www.strategicstudiesinstitute.army.mil/