An earthquake of 6.6 magnitude struck off the coast of Indonesia’s Molucca Islands on Sunday, followed by several smaller aftershocks, Reuters reported. However, no tsunami warning has been issued.

According to the United States Geological Survey, the quake struck 151 km west-northwest of Tobelo, situated in the northern Molucca island. The quake hit at a depth of 60 km and was followed by aftershocks of a magnitude of 5.0 to 5.1.

Samud Sergi, an official from the search and rescue agency in Ternate, said the quakes had not been felt in the city. Ternate is the largest city in the province of North Maluku.

A spokesperson for the emergency disaster agency in Tohomon in North Sulawesi said “they had felt nothing in the area and had heard of no damage or casualties”.

In a statement, the Pacific Tsunami Warning Center said there was no current tsunami threat based on available information.

In the most recent natural calamity, a tsunami that struck the country’s Sunda Strait last month, killing at least 429 persons. The tsunami had struck without warning after a portion of the volcanic Anak Krakatoa island fell into the ocean.

A 7.5 magnitude earthquake had struck off the Sulawesi island in September last year and caused a tsunami, killing hundreds of people. A series of earthquakes in July and August had killed nearly 500 people on the holiday island of Lombok.