Following the mainshock, a tsunami alert was issued for the nearby Makassar Strait, but was called off half an hour later. A localised tsunami struck Palu, sweeping shore-lying houses and buildings on its way. The combined effects of the earthquake and tsunami led to the deaths of at least 1,407 people and injured a further 632. This makes it the deadliest earthquake to strike the country since the 2006 Yogyakarta earthquake, as well as the deadliest earthquake worldwide so far in 2018. The Indonesian Agency for Meteorology, Climatology and Geophysics (BMKG) confirmed that a tsunami had been triggered with its height reaching an estimated maximum of , striking the settlements of Palu, Donggala and Mamuju along its path.