The foundation has been strongly linked with the controversial Gülen movement, led by the Islamic preacher Fethullah Gülen.
But the most constructive contribution is lead by Fethullah Gülen.
The school, affiliated with the movement of Fethullah Gülen, used the United States educational system and serves grades Kindergarten through 12.
Erdoğan blamed the investigation on an international conspiracy and vowed revenge on the Islamic community of the preacher Fethullah Gülen.
The Imam's Army (Turkish: İmamın Ordusu) is a book by Turkish journalist Ahmet Şık on the life and work of Fethullah Gülen and his Gülen movement.