A hillside in the Regent area of Freetown, the Sierra Leonean capital, collapsed following heavy weekend rains, covering many houses in mud.
Many people were asleep when the early morning mudslide occurred, the British Broadcasting Corporation (BBC), reported.
Sierra Leone’s Vice-President Victor Bockarie Foh said it was “likely that hundreds are lying dead”.
The total number of casualties is likely to rise.
Mr Foh told Reuters news agency that the disaster was “so serious that I myself feel broken”.
He said that the area was being cordoned off as people were being evacuated, including many still feared trapped in< their homes.