Disaster officials said the early morning quake, initially measured at a magnitude of 6.8, woke residents of towns such as the provincial capital of Ambon, about 40 km from the epicentre, but the geophysics agency ruled out a tsunami. According to Indonesia disaster mitigation agency (BNPB), the number of casualties is likely to increase as more information emerges from Maluku. Indonesia, which sits on the seismically active Pacific Ring of Fire, often experiences deadly earthquakes and tsunamis.