33 earthquakes hit Sikkim in a span of 13 hours, experts hint towards state's vulnerability
Telegraph | 7 February 2026
Sikkim was jolted 33 times in a span of 13 hours since 1am on Friday, and even though the magnitude of the quakes was 4.5 and less on the Richter scale, experts warned that the tremors were a grim reminder of the Himalayan state's vulnerability.
The Sikkim-Darjeeling region was recently upgraded to the highest seismic risk zone VI.
The epicentre of the first earthquake at 1.09am was Gyalshing in Sikkim.
“A total of 32 events (aftershocks) were recorded within 13 hours after the first earthquake,” Dr Saibal Ghosh, deputy director (general), Geological Survey of India in Calcutta, told The Telegraph.
Within four-and-a-half hours of the first earthquake, Sikkim and its neighbouring areas, including Darjeeling, Kalimpong and Siliguri, felt 12 aftershocks.
The National Centre for Seismology (NCS), Delhi, said the aftershocks with magnitudes from 2.2 to 4 on the Richter scale were recorded on the eastside from the epicentre of the main shock.
The epicentre of the first quake was at a depth of 10km and 31km away from Darjeeling, 42km from Gangtok and 68km from Siliguri.
“The event occurred on Teesta fault/lineament and south of the M 6.9, 18th September 2011 event,” read a statement by the NCS.
The earthquake on September 18, 2011, caused widespread damage in Sikkim and the neighbouring Darjeeling hills, killing nearly 100 people.
“This time, only two quakes were of magnitude 4 and 4.5 on the Richter Scale. Even though a series of jolts has released the pressure (in the tectonic plates), the event is a reminder for the public to be cautious. They need to be careful while constructing buildings,” said Ghosh.
No major damage has been recorded.
Last year, the Bureau of Indian Standards (BIS) updated its seismic zonation map and upgraded the Sikkim-Darjeeling region from Zone IV to Zone VI. Calcutta falls in Zone IV.
Earlier, the Himalayas had been split between Zones IV and V. Now, the entire region is in the highest risk category of Zone VI.
“It is very important that people start constructing buildings according to BIS standards,” said Ghosh.
Sikkim and Darjeeling now boast several hydro projects.
In Darjeeling, restrictions on building heights continue to be flouted.
Under Rule 162 of the West Bengal Municipality Building Rule 2007, hill civic bodies can sanction building plans up to a height of 11.5 metres. The municipalities have to get prior approval from the state government for construction up to 13.5 metres.
Experts say 11.5 metres roughly translates into a four-storey building.
In 2015, the Darjeeling municipality had identified 337 illegal high-rises in just eight of the 32 wards, which is a pointer to the scale at which the building norms were flouted.