Washington, Aug 10 (IANS): The allegation in Turkish press that the Washington-based think tank Wilson Center was behind a failed coup in Turkey is "absolutely not helpful", US State Department has said.

"I think this sort of conspiracy theory, inflammatory rhetoric ... is absolutely not helpful," Xinhua news agency quoted State Department spokeswoman Elizabeth Trudeau as saying on Tuesday. "Conspiracy theories get us nowhere."

The July 15 coup attempt in Turkey has left more than 200 people dead. The authorities have since detained more than 18,000 people.

Pro-government Turkish newspapers have implicated a group of academics who were attending a conference organised by the Wilson Center on the island of Buyukada near Istanbul at the time of the coup.

"There was nothing clandestine or sinister about the conference, which brought together specialists on Iran, Turkey, and the Middle East," Haleh Esfandiari, a senior scholar at the Woodrow Wilson, wrote in an article published on Tuesday on The Wall Street Journal.

Turkish authorities have accused US-based cleric Fethullah Gulen of orchestrating the coup attempt in coordination with a faction within the military.

An Istanbul court recently issued an arrest warrant for Gulen over his suspected role in the coup attempt, and Turkey has already sent its request to the US to extradite Gulen.

Turkey-US ties were strained by the failed coup amid Turkey's indication of US involvement in it. President Barack Obama denied any involvement in the coup attempt.

Turkey, a NATO ally for the US, is a major member of the US-led coalition in the fight against the Islamic State terrorist group.