MOSCOW (Sputnik) — According to the Turkish Dogan news agency, the Bulgarian authorities carried out the extradition at the Kapikule border crossing.
Ankara has accused Gulen and his followers of playing a key role in the mid-July attempted coup, which claimed lives of over 240 people.
Gulen, who has lived in the US state of Pennsylvania since 1999, has denied allegations that he orchestrated the July 15 coup attempt in Turkey.