A powerful magnitude 7.7 earthquake has struck Indonesia’s Flores region, according to the country’s Meteorology, Climatology and Geophysics Agency (BMKG), triggering an early tsunami warning for several areas. The US Geological Survey also recorded the earthquake at magnitude 7.7.

The quake was centered at 8.41 degrees south latitude and 121.39 degrees east longitude at a depth of 15 kilometers, according to BMKG. The shallow depth could mean strong shaking in areas close to the epicenter.

First visuals from the affected region showed buildings cracking and sustaining damage as the powerful earthquake rocked Flores. Video footage also appeared to show water receding in some areas.

Several aftershocks have followed the main earthquake, including tremors measured at magnitudes 6.2, 6.5 and 4.8 in the same area, according to BMKG. Further aftershocks, including magnitude 5.9 and 6.1 earthquakes, were also reported.

BMKG issued an early tsunami warning for East Nusa Tenggara, South Sulawesi, West Nusa Tenggara and Southeast Sulawesi.

Authorities are assessing the impact of the earthquake, while further information on possible casualties and damage is awaited.

The tsunami warning remains in place as authorities assess the potential threat along affected coastlines.