The national disaster management agency said 102 people were confirmed dead in Aceh province since the magnitude 6.5 temblor hit Wednesday morning.
The chief of the national search and rescue agency’s operations department said some victims are believed to still be buried under the rubble of hundreds of toppled buildings.
"Teams continue to evacuate earthquake victims buried under the ruins of buildings," Al-Husain was quoted as saying by kompas.com.
According to official figures, more than 750 people were injured -- 136 of them seriously -- while at least 3,267 were displaced.
The disaster management agency said that 94 people were confirmed dead as of 8.30 p.m. (1330GMT), while more than 620 others sustained injuries -- 128 of them severely.
Local authorities had earlier declared an emergency until Dec. 20.
Aceh's army chief, Tatang Sulaiman, said Wednesday that troops and police from three districts were deployed to speed up ongoing efforts to rescue victims.
Indonesia lies within the Pacific’s "Ring of Fire", where tectonic plates collide and cause frequent seismic and volcanic activity.
In June, a magnitude 6.5 tremor damaged buildings in western Sumatra Island, with its shocks reportedly felt in parts of Singapore and peninsular Malaysia to the north.
On Dec. 26, 2004, a magnitude-9.1 earthquake struck the eastern coast of Sumatra, causing a tsunami that killed around 230,000 people -- the majority in Aceh -- as it tore along the coasts of Sri Lanka, India, Malaysia, Indonesia and Thailand.