The India Meteorological Department (IMD) has issued a red alert following heavy rainfall and a sharp rise in water levels of the Teesta River, which flows downstream from Sikkim into northern Bangladesh.

On Saturday, the IMD warned of potential floods and landslides in Sikkim’s Mangan, Gyalshing, and Soreng districts, Indian outlet Economic Times reports.

In a public advisory, Gangtok's district magistrate urged residents not to panic but to stay alert, assuring that updates would be provided as the situation unfolds.

Originating from Chhangu Lake in the Himalayan region of Sikkim, the Teesta River flows across the border into Bangladesh through Nilphamari's Kaliganj. Therefore, upstream flooding along the Teesta in India often affects downstream regions in Bangladesh as well.

Bangladesh’s Flood Forecasting and Warning Centre (FFWC) has said that water levels in the Teesta, Dharla, and Dudhkumar rivers in the Rangpur Division may continue to rise over the next three days, with the Teesta potentially crossing the danger mark.

Due to heavy rainfall upstream, rivers in the Sylhet and Mymensingh divisions are also expected to rise over the next two days.

Sardar Uday Raihan, the executive engineer at the centre, told bdnews24.com that water levels in rivers across the Sylhet Division are still rising.

“Heavy to very heavy rainfall is expected upstream. As a result, river levels in Sylhet and Mymensingh divisions may cross the danger mark over the next two days. The levels may begin to recede from the third day. In Chattogram division, river levels may begin to fall starting tomorrow,” he said.

According to the forecast, the water levels in the Sari-Goyain, Jadukata, Dhalai, Someshwari, and Manu rivers in Sylhet and Mymensingh may rise and cross the danger mark in the next two days. This could lead to flooding in low-lying areas of the Sylhet, Sunamganj, Netrakona, and Moulvibazar districts.

The Surma and Kushiyara rivers are also rising, and this trend may continue for the next two days before declining to flow below the danger level.

In the Rangpur Division, the Teesta, Dharla, and Dudhkumar rivers may see rising water levels over the next three days, with the Teesta possibly flowing near the warning level.

The forecast also notes that the Gomti, Muhuri, Feni, Halda, Sangu, and Matamuhuri rivers in the Chattogram Division are expected to remain stable for the next 24 hours, with levels likely to decrease over the following two days.

In the Ganges-Padma basin, water levels may rise for five days but are expected to stay below the danger mark.

Rivers in the Brahmaputra-Jamuna basin may also rise for the next five days, though they are forecast to remain below the danger level.