At least 100 people injured and more than 2,000 evacuated, officials say, as temblor strikes about 37 kilometres offshore northeast of Ambon in Maluku province.
At least 20 people were killed and dozens injured on Thursday in a strong earthquake that rocked Indonesia's remote Maluku islands, triggering landslides that buried at least one of the victims, the disaster agency said.
Terrified residents ran into the streets as buildings fell in around them when the 6.5-magnitude quake hit in the morning.
"At least 100 people were injured and more than 2,000 evacuated," national disaster mitigation spokesman Agus Wibowo said, who gave the latest death toll in a statement.
Among those killed was an infant, he said.
Parts of a building at an Islamic university collapsed in Ambon, the capital of Maluku province.
Local disaster official Albert Simaela said a teacher was killed there when parts of the building fell on her.
Simaela said a main hospital in Ambon was damaged and patients were evacuated to tents in the hospital's yard.
'Everybody was panicking'
"I was asleep with my family when suddenly the house started to shake," an AFP reporter in Ambon said.
"The quake was really strong. We ran from our house and saw the neighbours fleeing too. Everybody was panicking."
Indonesia experiences frequent seismic and volcanic activity due to its position on the Pacific "Ring of Fire", where tectonic plates collide.
Last year, a magnitude 7.5 quake and a subsequent tsunami in Palu on Sulawesi island left more than 4,300 people dead or missing.
On December 26, 2004, a devastating magnitude 9.1 earthquake struck off the coast of Sumatra and triggered a tsunami that killed 220,000 throughout the region, including around 170,000 in Indonesia.