A strong earthquake with an estimated magnitude of 6.1 on the Richter scale struck Friday off the Indonesian island of Sulawesi, the observatory in Hong Kong said.
The quake hit at 10:50 pm (1450 GMT) and was initially determined to be centred in the Molucca Sea, about 200 kilometres (124 miles) south of Manado, the main city on the north-eastern tip of the island, the observatory said.
There were no reports of damage or casualties.