A moderate earthquake centred in the Indian mountain state of Sikkim on Tuesday sent people running from their homes in the neighbouring eastern state of West Bengal, officials and witnesses said.

An Indian Meteorological Department official told Reuters that the 5.7-magnitude earthquake's epicentre was over 1 120km north of the eastern city of Calcutta and occurred at 6.25am (00h55 GMT).

"Lots of people panicked and ran out of their homes. But I have not heard of casualties," local journalist Niraj Lama said from the hill town of Darjeeling in West Bengal, which is close to Sikkim.

Witnesses in central West Bengal also felt the earthquake.