A Pennsylvania-based Muslim cleric accused of fomenting a failed coup in Turkey in July spoke at length for the first time on Thursday about the withering post-coup crackdown on his supporters and other dissidents by the Turkish government, calling it “a display of hate and rage.”

“Right now, all critical voices are silenced in Turkey and only the voice of those in power is heard,” said the cleric, Fethullah Gulen, who has lived in self-imposed exile in rural Pennsylvania since 1999.  “These days will be recorded as dark pages in world history,” he said, in pre-taped video remarks delivered to the World Affairs Council in Philadelphia.

Turkish officials have accused Gulen of orchestrating the bloody summer insurrection, which left hundreds of people dead and raised questions about Turkish President Recep Tayyip Erdogan’s control over the state.  The authorities in Turkey have arrested tens of thousands of people and carried out a wide-ranging purge they say is aimed at ridding state institutions of Gulen followers. The government is also targeting people it views as opponents or not sufficiently loyal, including journalists, critics say.

In a sign of the bracing scale of the purge, the Turkish authorities recently announced they were building 174 new prisons, to “meet the unanticipated increase in the number of convicts,” according to the Justice Ministry.

Gulen, 77, who has a global following and presides over a secretive, international network that includes charities, schools, universities and business associations, has denied any involvement in the coup attempt.

The incendiary feud between Gulen and Erdogan, who were formerly political allies, is increasingly playing out in the United States. Turkey’s government, a major U.S. ally, has requested the Obama Administration extradite Gulen, and in recent weeks, Turkish officials have lobbied members of Congress to support the extradition request.

In his remarks Thursday evening, Gulen seemed to encourage Turkey’s western allies to punish the Erdogan government for its conduct after the coup attempt, including with sanctions.

“I think at some point international human rights organizations, intellectuals, legal organizations may react and push states to act, saying enough is enough,” he said. “Perhaps in realizing that they cannot afford to be completely cut off from the world, Turkish leaders might change course.”

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