Fethullah Gulen, the Turkish cleric accused by the Erdogan administration of orchestrating the July 2016 attempted coup in Turkey, has died aged 83.

The preacher, who had long lived in self-imposed exile in the US, passed away on the evening of October 20 after being admitted to a Pennsylvania hospital, according to Herkul, a website that publishes his sermons.

Gulen was the spiritual leader of the Gulen movement, an Islamic community with followers in Turkey and worldwide. Known to his supporters as Hodjaefendi, or “respected teacher”, he was the son of an Islamic preacher, or imam, and studied the Koran from infancy.

Turkey’s President Recep Tayyip Erdogan, who during his political rise was initially an ally of Gulen, came to describe the Gulen movement as the Fetullah Terrorist Organistion, or FETO, though to its followers it is known as Hizmet, which means “service” in Turkish. To much enduring scepticism, Erdogan directly blamed Gulen for the attempted putsch, in which rogue troops commandeered warplanes, tanks and helicopters and 251 people lost their lives.

However, Gulen condemned the coup attempt “in the strongest terms”. “As someone who suffered under multiple military coups during the past five decades, it is especially insulting to be accused of having any link to such an attempt,” he said in a statement.

Gulen later hit out at Erdogan for throwing thousands of people in jail on flimsy grounds that they were somehow connected to him or his movement. “The last year has taken a toll on me as hundreds of thousands of innocent Turkish citizens are being punished simply because the government decides they are somehow ‘connected’ to me or the Hizmet movement and treats that alleged connection as a crime,” he said in 2017 on the first anniversary of the failed coup.

Speaking at a press conference in Ankara on October 21, Foreign Minister Hakan Fidan said intelligence sources had confirmed Gulen's death. He described the cleric as the leader of a "dark organisation".

"Our nation's determination in the fight against terrorism will continue, and this news of his death will never lead us to complacency," Fidan told a press conference.

In rising to prominence, Gulen argued that young people in Turkey had lost their way. Education was the best response, he said. His movement became well known for running schools around the world.

Erdogan turned on the movement in 2013. He moved to shut down its hundreds of schools in Turkey and “cleanse” the government of the “cancerous” Gulenists, whom he said had formed a "state within a state". Hizmet was formally declared a terrorist organisation in May 2016.

In the post-coup crackdown that targeted Gulen's followers, at least 77,000 people were arrested, while 150,000 state workers including teachers, judges and soldiers were suspended under emergency rule.

Gulen, born in Erzurum, in eastern Turkey, escaped the Erdogan regime’s clutches because he had moved to the US as far back as 1999. After the failed coup, Ankara grew furious and frustrated with the US, which refused to extradite him unless evidence of his involvement in the attempt at toppling Erdogan was presented.

Speaking in 2017 in his gated compound in Pennsylvania’s Pocono Mountains, Gulen said in a Reuters interview that he had no plans to flee the US to avoid any change of heart by Washington on Ankara’s request to extradite him. Even back then, he was described as frail, walking with a shuffle and keeping his doctor close at hand.