Nairobi - The United States Embassy in Kenya warned its citizens Monday that "credible information indicates Westerners may be targeted by extremists."
The warning comes just weeks after a deadly al-Shabaab attack on an upmarket hotel in Nairobi in which a US citizen was amongst those killed.
The embassy said targets could include several parts of the east African country, listing Nairobi, Naivasha, Nanyuki, and coastal areas.
It urged US citizens to be vigilant, especially "in shopping malls, hotels, and places of worship."
Jihadist group al-Shabaab regularly targets places frequented by foreigners or government officials in both Somalia and neighbouring Kenya.