Fathur Rahman, an official with the Maumere search and rescue agency, said initial reports indicated that six people were injured, with two others still buried.

"According to the reports we have received, 20 people have died, six are injured, and two are still buried," Rahman said by telephone while travelling by boat to the affected area.

Search and rescue operations were ongoing as authorities worked to assess the full extent of casualties and damage caused by the earthquake.