A massive landslide hit Sikkim's Mangan district in the early hours of Sunday (September 6, 2026), partially blocking the flow of two rivers, officials said.

A substantial portion of the hillside along a new road cutting of the Naga-Tosa Road in the Naga Forest area, opposite the Theng Tunnel, collapsed near the confluence of the Teesta and Chyakoong rivers in Chungthang subdivision, they said.

The landslide partially blocked the flow of both rivers, they added.

No casualties or injuries have been reported so far, while the extent of damage to property, if any, is being assessed, officials said.

The river levels at Sankalang and Phidang outposts are currently normal, though the water remains muddy, they said.

The local administration has been directed to maintain continuous monitoring of water levels and immediately report any significant changes, they said.