Gunfire has been reported on Monday at the U.S. Embassy in Port-au-Prince, Haiti.
In a travel alert, the US State Department said that gunfire had come from the "rear entrance to the embassy" in Port-au-Prince.
It said the staff had taken shelter inside the embassy.
"If you are traveling to the embassy, find a safe area to shelter," it wrote on Twitter.
State Department officials did not immediately have further details on the incident, including whether it was ongoing.
There have been no reports of injuries.