From afrol News - How Kenya, Seychelles avoided tsunami disaster:
As the fist signs of disaster in Asia were becoming clear, the US seismologists rapidly understood that the tsunami was heading towards the African coast. The American embassies in Mauritius and Madagascar were warned, which again passed the alert to national authorities around the region. Seychelles took an early lead, also confirming to Kenyan authorities that they indeed could expect a devastating wave.
No emergency plans however exist in these countries on how to handle a tsunami - the region almost never experiences such natural disasters. In Seychelles, the National Disaster Committee immediately set up a base at the Police Command Centre in Victoria to monitor what was happening. It instructed the Seychelles Broadcasting Corporation to send out alerts to warn members of the public.
