The epicenter of the earthquake, which struck at 7.02 p.m. WIB (West Indonesia Time), was located in the sea, 59 kilometers northeast of Tojo Una-Una at a depth of 10 kilometers, the agency said.
An earthquake of 5.9 magnitude had also hit the district earlier in the day.
The earthquake, which struck at 10.52 a.m. WIB (West Indonesia Time), was centered 55 kilometers northeast of Tojo Una-Una district, at a depth of 10 kilometers, BMKG reported.
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“The earthquake was a shallow earthquake caused by deformation due to local fault. The result of source mechanism analysis shows the earthquake had normal fault mechanism,” head of the BMKG Earthquake and Tsunami Center, Bambang Setiyo Prayitno, said in a statement released on Monday.
Central Sulawesi had borne the brunt of a 7.4-magnitude earthquake on September 28, 2018.
The strong earthquake, which was followed by a tsunami and soil liquefaction in Palu, the capital of Central Sulawesi province, had claimed 2,102 lives, injured 4,612, and rendered 680 others missing.
A total of 68,451 homes had incurred serious damage, while 78,994 people had been displaced by the quake.
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