An earthquake measuring 5.5 on the Richter Scale jolted West Sumatra on 00.38 am local time on Monday followed by another tectonic temblor of 5.0 in West Nusa Tenggara (NTB), ANTARA reported. According to the meteorology and geophysics agency (BMG), the first earthquake in West Sumatra was located at 1.66 degrees southern latitude - 99.33 degrees Eastern longitude at a depth of 23 kilometers below sea level, and 63 km southwest of the Siberut Mentawai Islands, West Sumatra, on Monday. Meanwhile, the West Nusa Tenggara earthquake was located at 7.82 degrees southern longitude - 118.63 degrees eastern latitude at a depth of 26 km and 73 km northwest of Raba-NTB.