The landslide took place in the Simaltal area along the Narayanghar-Mugling road in the Chitwan district on Friday. Of the 54 people, three people had swam to safety after the bus was swept away.

The Kathmandu-bound Angel bus from Birgunj was carrying 24 people including seven Indian nationals, while the Gaur-bound Ganpati Deluxe bus from Nepal's national capital was carrying 30 people.

As heavy mudslides, triggered by incessant rainfall, hit the buses, they plunged into the Trishuli River on Madan-Ashrit Highway in central Nepal.

Bodies of 19 persons have been recovered from the twin bus accident so far and of those, four are of Indian national, news agency PTI reported citing Armed Police Force sources.

Reportedly, five male dead bodies are yet to be identified.

Rescue operations which have been taking place since the day of the incident were continuing on Thursday as well, with local authorities coordinating with Indian officials in Bihar and Uttar Pradesh to carry out the rescue works.

During a search which was carried out by security personnel, the dead body of one 27-year-old Vivek Kumar was recovered. The bodies of the three others -- Rishi Pal Shah (28), Jay Prakash Thakur (30) and Sajad Ansari (23) -- were found at the accident site.

Authorities have used high-quality sonar cameras, powerful magnets and water drones to aid the rescue operations.

Notably, Nepal has generally fast-flowing rivers due to its mountainous terrain. In addition, the heavy downpours during monsoon season further added to the water bodies, turning them murky brown. This makes it even more difficult to see the wreckage.

Nepal experiences monsoon season from June to September, with incessant rains often triggering landslides in the mountainous Himalayan country.