Indonesian disaster agency spokesman Sutopo Purwo Nugroho says the magnitude 7.5 Sulawesi earthquake caused a tsunami that hit the provincial capital of Palu and another city, Donggala.
He said in a live TV interview Friday that houses were swept away and families are reported missing. Sutopo said communications with the area in central Sulawesi are down and the search and rescue effort is being hampered by darkness.
The U.S. Geological Survey said the shallow quake was centred at a depth of 10 kilometres. A spokesman for Indonesia's geophysics agency says the powerful earthquake caused a tsunami, apparently after the agency lifted a tsunami warning.
Indonesian TV showed a smartphone video of a powerful wave hitting the provincial capital, Palu, with people screaming and running in fear.