Singapore’s National Environment Agency (NEA) has put the quake’s magnitude at 6.5 on the Richter scale, warning about possible tsunamis in the region, Asia One reports.
At least five earthquakes have shaken Indonesia in recent hours, the USGS reported, adding that the strongest, with a magnitude of 6.1 on the Richter scale, struck only 81 kilometers from the nearest city.
The 6.1 magnitude quake struck 81 from of the city of Padang Sidempuan, which has a population of over 200,000 people, and 111 kilometers from the city of Sibolga in the western part of Indonesia. The epicenter of the quake was reportedly at a depth of 75 kilometers.
It was almost immediately followed by another one, with a magnitude of 4.8 on the Richter scale, 147 kilometers from another Indonesian city, Sabang, with over 150,000 residents. Two more, with a magnitude of 5.2 and 4.9, hit the same area minutes later.
Four hours earlier, a 4.3 magnitude earthquake struck 260 kilometers from the town of Saparua, eastern Indonesia.