Shots have been fired from a vehicle at the US embassy in Turkey's capital Ankara.
A window in a security cabin was hit but no one was hurt, both the police and local media reported.
A Turkish presidential spokesman tweeted that it was "an attempt to create chaos."
Relations between the two countries have been strained over the trial of an American pastor in Turkey as well as economic disputes.
Turkey also wants the US to hand over Muslim cleric Fetullah Gulen whom it says masterminded a failed coup against President Erdogan in 2016.