An earthquake measuring 5.4 on the Richter scale shook Indonesia's Nias Island on Thursday night but there was no immediate report of casualties or material damage.
The epicenter of the quake which struck at 07:04 pm was in the sea, 41 km south west of the island at a depth of 25 km, Antara news agency Friday quoted spokesman for the Bengkulu Meteorology and Geophysics Station Sujud as saying.
On Wednesday, an earthquake measuring 6.2 on the Richter scale also rattled the island, leaving one person dead and four others injured.
Wednesday's temblor was also believed to have caused cracks in tens of buildings in Gunung Sitoli sub district on the island, spokesman for the Medan Meteorology and Geophysics Office Rifwar Kamin said.
The epicenter of the quake was also in the sea, about 24 km north west of the island at a depth of 10 km, he said.