A major traffic jam was witnessed on NH 10 on Sunday as several landslides blocked Sikkim's arterial highway that connects the Himalayan state with the rest of India, BRO sources said.

However, many light vehicles were seen taking a detour via Darjeeling in Bengal to reach their destinations, they said.

Heavy rain triggered a series of small landslides since Saturday night and a major one on Sunday morning in the 29th Mile area between Teesta and Rambi in Bengal, completely blocking the highway.

Serpentine queues of vehicles were witnessed for more than 1 km on both sides of the landslide spot, the sources said.

Border Roads Organisation (BRO) workers and officials were engaged in clearing the highway and hope to open it for one-way traffic during the day but continuous rainfall is hindering the work, they said.

The area had earlier witnessed frequent landslides during monsoon. The Himalayan region has been receiving heavy rain in the last one week.