After the first quake of 6.4 magnitude struck Tezpur at 7.51 am on Wednesday, a total of 18 aftershocks hit the district and its nearby areas on both sides of the Brahmaputra in central Assam, an official said on Thursday morning.
A total of eight quakes jolted the state since Wednesday night and all originated in and around Tezpur, the National Centre for Seismology (NCS) said in its bulletin.
The strongest one was of 4.6 magnitude that hit at 1.20 am, forcing the people to run out of their homes in panic.
The other tremors were of 2.8, 2.6, 2.9, 2.3, 2.7, 2.7 and 2.8 magnitudes, hitting the state at 9.38 pm, 12.24 am, 1.10 am, 1.41 am, 1.52 am, 2.38 am and 7.13 am, NCS said.
There was no immediate report of any damage to any structure, or injury to the people due to these aftershocks.
Severe damage to buildings and roads was reported from across Assam, following the first earthquake, tremors of which were felt across the Northeast, parts of West Bengal, Bhutan and Bangladesh.