A magnitude 5.4 earthquake struck near the Sikkim-Nepal border on Monday at 8:49pm.
Aftershocks were felt in north Bengal, Assam, and some other parts of Bihar.
Tremors were felt in some parts of Nepal, Bhutan, Meghalaya, Nagaland and Arunachal Pradesh.
There are no reports of any damage or deaths due to the earthquake that have been reported so far.
The epicentre of the earthquake was 25 km east-southeast (ESE) of Gangtok, Sikkim. The earthquake struck at a depth of 10 km from the surface.
According to the PMO's office, Prime Minister Narendra Modi is speaking to the chief ministers of all four affected states.