The Border Roads Organisation (BRO) under the ministry of defence on Monday rescued five persons in an SUV stuck on a rain-hit road in Sikkim between huge boulders and a waterfall-like cascade.

They also managed to retrieve the vehicle and cleared the road that had remained blocked by boulders for around seven hours.

Sources said because of heavy rains caused by the southwest monsoon on Sunday night, a small cascade of water swelled into a massive torrent of a waterfall and washed away a part of the road that connects Singtam with Dikchu, both in Gangtok district in the eastern part of Sikkim.

It also brought down some boulders which blocked the road.

Unaware of the change in weather and road conditions, an SUV with five occupants — a driver and four passengers — reached the area. As the driver tried to cross the waterfall around 3.30am on Monday, the force of water proved too much for the vehicle to resist. The SUV was washed away by the water but luckily got stuck in some boulders, which prevented the vehicle, and the five persons, from falling into a deep gorge.

Those inside the vehicle couldn’t come out as the doors were stuck by boulders on one side and a gush of water on the other.

As the news spread, a team from the nearest camp of the BRO reached the spot by around 4.30am. “The BRO personnel ensured that the SUV did not slip into the gorge, while at the same time, they tried to extricate the persons. After an hour’s efforts, all five were rescued from the vehicle around 5.30am,” said a source.

However, the strong force of the water prevented them from taking out the SUV. Eventually, earthmoving equipment of the BRO was brought to the spot.

The machinery managed to pull out the SUV around 9.30am.

“After the vehicle was retrieved, the BRO took the task to clear the debris and open the road. Excavators were pressed into work as traffic had halted along the stretch. Around 10am, vehicular movement was restored on the route,” the source added.

The torrential downpour caused by the monsoon also caused a flash flood in Rambhi of Bengal's Kalimpong district on Monday early morning. The force of water, along with slush, gushed down the hills and damaged three houses.

Weather experts said the southwest monsoon has reached most parts of sub-Himalayan Bengal and Sikkim and also neighbouring parts of Bihar.

“Rainfall has started in this region, along with some other parts of the country. There is a forecast of heavy rainfall in Sikkim and also the adjoining areas of Bengal,” said a source.