The US Department of Justice will dispatch a team to Turkey in the coming days to pursue allegations by the Turkish government of criminal activity by Fethullah Gulen, according to a US media report.
If true, the move, first reported on Friday by Bloomberg News citing a US administration official, would mark the first sign of progress in Turkey's attempts to have the Pennsylvania-based Turkish-born religious leader extradited.
The government of Turkish President Recep Tayyip Erdogan has accused Gulen's network of being behind a coup attempt last month, a charge he has strenuously denied.
"Sooner or later, the US will make a choice. Either Turkey or FETO," Erdogan said last week, referring to Gulen.
However, the Washington Post newspaper, quoting an official at the US justice department, reported on Friday that the extradition request refers only to alleged activities before the failed coup attempt.
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"It's actually tied to allegations of certain alleged criminal activities that pre-date the coup," the official said.
"At this point, Turkish authorities have not put forward a formal extradition request based on evidence that he was involved in the coup."
US officials are "working alongside their Turkish counterparts to make sure we understand everything contained in the evidence", according to the justice department official.
"If there is probable cause for extradition, ultimately a court will determine whether the evidence is sufficient. ... We are still a way down the line from even knowing whether that's possible."
US officials have said that even if the justice department decides extradition is warranted, a court case and possible appeals could take several years.
Arrests in Azerbaijan
In another development on Friday, officials in Azerbaijan said they had arrested four men over suspected ties to Gulen.
The four are accused of an "abuse of power" while working for a mobile phone company for having passed on private information about subscribers and their call history, Azeri prosecutors said.
During a search of the home of one of the accused, investigators discovered "religious literature, disks, brochures containing speeches by Fethullah Gulen and other documents", they said in a statement.
|Tension between Turkey and Gulen's network has risen since last month's failed coup [Sedat Suna/EPA]
A close ally of Turkey, Azerbaijan earlier this week opened a criminal investigation into supporters of Gulen.
Azerbaijan last month shut down a private television channel over plans to broadcast an interview with Gulen, "in order to avoid provocations aimed at damaging the strategic partnership between Turkey and Azerbaijan".
Reports from Denmark
The Azeri move came shortly after Danish media reported that hundreds of Turks in Denmark had withdrawn their children from schools with alleged links to Gulen.
A document circulating on Facebook listed 14 private schools in Denmark as being linked to Gulen and urged parents to "Save your children from Fethullah Gulen's terror organisation's schools", according to a translation from Turkish by broadcaster TV 2.
A total of 366 students had been pulled out of the schools after the summer break, the broadcaster said.
Gulen's Hizmet organisation has affiliated schools around the world, including in the former Soviet Kazakhstan, normally funded by wealthy Turkish businessmen.