“The FBI believes that the Dokumacılar Group was connected to the suicide attack on March 19, 2016, which occurred in Istanbul that killed two U.S. citizens and wounded one other,” it stated.

The Dokumacılar Group was formed by 60 Turkish citizens from Adıyaman and crossed into Syria after receiving training from ISIL, according to correspondence from the U.S.

The documents also stated that the cell also played a role in attacks on a Peoples’ Democratic Party (HDP) rally in Diyarbakır on June 5, 2015, as well as massive suicide attacks in Suruç on July 20, 2015 and Ankara on Oct. 10, 2015.

Turkish police also shared the email address of the İstiklal suicide bomber, Mehmet Öztürk, with officials in the U.S.