Today, Friday, the American missions in Turkey announced the suspension of services to American citizens and the suspension of granting visas, and said that they had received "reliable information" about the possibility of "terrorist" attacks.
The embassy said in a statement that the US mission in Turkey had received "credible" reports regarding possible terrorist attacks and kidnappings targeting American citizens and other foreigners in Istanbul, including the US Consulate General and other possible sites in Turkey.
She advised American citizens "to be very careful in places where Americans or foreigners may gather, including large buildings that house offices or shopping centers."
The last such suspension was made by the United States in 2017, when the US embassy announced the suspension of all visa services at its headquarters and consulates in Turkey, except for immigrants.
This came days after a Turkish court ruling issued an employee of the US Consulate General in Istanbul on various charges, including espionage.