India: Strong tremors felt in Kolkata

Tremors were felt across Kolkata and adjoining areas of West Bengal on Friday afternoon after a moderate earthquake struck Bangladesh, prompting residents to rush out of homes and office buildings as a precaution.

The earthquake, measured at magnitude 5.3 by the US Geological Survey (USGS) and 5.4 by the Bangladesh Meteorological Department (BMD), occurred at around 1:30pm. According to the USGS, the epicentre was located approximately 188 kilometres from Dhaka at a depth of 9.8 kilometres.

The BMD said the tremor was recorded southwest of its Seismic Centre in Dhaka’s Agargaon area.

In Kolkata, people were seen gathering in open spaces shortly after the shaking was felt. Many residents reported noticeable movement inside buildings.

Recounting her experience, Swagata, a resident of the city, said furniture and household objects began shaking suddenly.

“We were sitting on our sofa when we suddenly felt the tremors. We rushed out of our house. The sofa and fan were shaking, and a bottle kept on a table fell down. All of us have rushed downstairs,” she said.

The relatively shallow depth of the quake — 9.8 kilometres — is significant. Shallow earthquakes are generally more dangerous than deeper ones because seismic waves travel a shorter distance to the surface, resulting in stronger ground shaking and potentially greater damage.

According to USGS classifications, earthquakes occur at depths ranging from the surface to about 700 kilometres underground. For scientific purposes, they are divided into three categories: shallow (0–70 km), intermediate (70–300 km), and deep (300–700 km). Earthquakes deeper than 70 km are often referred to as deep-focus events.

Earlier in the day, a separate earthquake of magnitude 2.7 struck Namchi in Sikkim, the National Centre for Seismology (NCS) said. The tremor occurred at 12:02pm at a depth of 5 kilometres.

Authorities have not reported any immediate damage or casualties in connection with either of the tremors.

- with inputs from ANI