Toner said the first batch "did not, we believe, constitute a formal extradition request."
He added: "We subsequently received more documents. We`re looking through them ... and I don`t think they`ve reached that determination yet."
The U.S. Justice Department is the main agency poring over the documents to see whether they amount to a formal extradition request for Gulen, who has lived in self-imposed exile in Pennsylvania since 1999.
Turkish officials, including Foreign Minister Mevlut Çavuşoğlu, have warned that ties with the United States will be affected if it fails to extradite Gulen.
The NATO member plays an important role in the U.S-led fight against Islamic State of Iraq and the Levant (ISIL). But Washington has said Ankara must provide clear evidence of Gulen`s involvement in the failed military coup attempt before any extradition process can move forward.
Gulen has denied plotting against Turkey and has condemned the coup attempt.
Toner said the United States had offered to help Turkey with investigating the coup attempt. He did not say whether Turkey had responded to the offer.
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