The U.S. Embassy in Kampala, Uganda, issued an alert this week to Americans that it is looking into reports that an attack similar to the one at a Kenyan mall could soon occur in the the city.
The embassy's statement said there were no specific details about a possible date or location of a "Westgate-style attack." It didn't say where the reports were coming from.
A U.S. official with direct knowledge of the latest information told CNN the notice was sent "out of an abundance of caution." The U.S. is still vetting the information, the official said, to see if there is any truth behind it.
Washington doesn't think the Westgate attackers or al Qaeda is planning the potential attack, the U.S. official said.
At least 67 people were killed by multiple attackers during the four-day siege at the mall in Nairobi last month. The terrorists who attacked the mall claimed to be members of Somalia-based Al-Shabaab.
The embassy in Kampala - Uganda's capital - urged Americans traveling to the country or living there to register with the State Department's Smart Traveller Enrollment Program.
-CNN's Barbara Starr and Elise Labott contributed to this report.