The State Department on Saturday criticized Turkey over attempts to intimidate and threaten a New York Times correspondent whose reporting about Turks recruited by the Islamic State, the militant group, has deeply offended Turkey’s president.

Personal attacks conveyed through email and Twitter aimed at the correspondent, Ceylan Yeginsu, have intensified in Turkey since the publication of her article on Tuesday about the Islamic State’s recruitment efforts.

On Friday, Turkish newspapers controlled by allies of the president, Recep Tayyip Erdogan, published front-page photographs of Ms. Yeginsu and asserted that she was a traitor and foreign agent who was seeking to falsely imply that Mr. Erdogan is a closet supporter of the Islamic State.

Turkey, along with the United States and most other countries, regard the group as a terrorist organization.