UK tourists are among holidaymakers being advised to avoid the surrounding area, but not including the tourist areas of Diani or Moi international airport which serves the city.
There is a high threat from terrorism, including kidnapping. The main threat comes from extremists linked to Al Shabaab, a militant group that has carried out attacks in Kenya in response to Kenya's military intervention in Somalia.
There has been a spate of small-scale grenade, bomb and armed attacks in Nairobi (especially the area of Eastleigh), Mombasa, and North Eastern Province.
You should take care in public places where people gather, and exercise a heightened level of vigilance.
In the last few days the Kenyan government has pledged to step up security for tourists following a number of terrorist-related incidents.
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