Jakarta: An earthquake with a magnitude of 7.7 jolted off the coast of Flores Island in Indonesia early Saturday, the country's Meteorology, Climatology and Geophysics Agency (BMKG) said.

The epicenter was located 36 km northeast of Mbay, East Nusa Tenggara province, with a depth of 15 km, according to the BMKG, which has issued a tsunami warning following the tremor, Xinhua news agency reported.

Strong tremors were felt in several areas, prompting many panicked residents to rush into the streets for safe shelter, local media reported.

There were no immediate reports of casualties.

The initial jolt was followed by strong aftershocks in the same area, including one with a magnitude of 6.1.

Indonesia's Meteorology, Climatology, and Geophysics Agency (BMKG) warned there was a possibility of tsunami waves being generated by the quake.

"Tsunami modelling results indicate that this earthquake has the potential to generate a tsunami in the provinces of East Nusa Tenggara, South Sulawesi, and West Nusa Tenggara," BMKG earthquake and tsunami director Wijayanto said.

Indonesia sits on the Pacific "Ring of Fire" and is home to more than 120 active volcanoes, making it one of the world's most volcanically active countries. 

Among Indonesia's history of deadly quakes is a devastating 9.1-magnitude tremor in 2004 that struck off the coast of Sumatra and triggered a tsunami that killed 220,000 throughout the region, including about 170,000 in Indonesia.

In 2018, Indonesia’s Lombok island was hit by a powerful earthquake, followed by a series of aftershocks over the following weeks. The disaster killed more than 550 people across Lombok and neighbouring Sumbawa, both popular tourist destinations.

Later that year, another major disaster struck Sulawesi. A 7.5-magnitude earthquake hit the island, triggering a devastating tsunami in Palu. More than 4,300 people were killed or reported missing in the disaster.