A medium-intensity earthquake shook Arunachal Pradesh early on Wednesday.
There were no reports of any damage to property or casualties in the quake that occurred at 1:45 am.
While the IMD said the quake measured about 5.9, the United States Geological Survey pegged it at 6.1.
The epicentre of the quake was about 40 kilometres southeast of Along, and 180 kilometres southwest of the state capital Itanagar.
State Director General of Police S V K Singh, who himself was awakened by the temblor, said he contacted the superintendents of police of all districts but no damage was reported from anywhere.
The districts extend from areas bordering Bhutan, Tibet and Myanmar, he said.
“Though people panicked there are no reports of any damage,” he said.
Prof Trilochan Singh, who served as a geologist of Wadia Institute of Himalayan Geology for decades, described it as “shallow earthquake”, considered dangerous for its impact within a radius of 40-50 km.
Mild earthquakes often occur in this Himalayan state, located in seismic zone 5, Singh said.
The earthquake zoning map of India divides the country into 4 seismic zones (Zone 2, 3, 4 and 5) unlike its previous version, which consisted of five or six zones.
According to the present zoning map, Zone 5 expects the highest level of seismicity whereas Zone 2 is associated with its lowest level.
A strong 6.3-magnitude earthquake also struck Tibet close to India early on Wednesday, authorities said.
There were no immediate reports of casualties.
The quake, which struck at 4:15 AM, jolted Medog county in Nyingchi city which is located close to Arunachal Pradesh.