Rescuers in Nepal ruled out chances of finding survivors in last week's landslide that swept two passenger buses carrying 65 people into a river swollen by heavy rain, authorities said on Monday.

Hundreds of security personnel resumed search operations early on Monday to locate the buses and 55 passengers who remained missing, over 72 hours after the accident.

Searchers scouring Friday's accident site in Chitwan district, about 86 km (53 miles) west of the capital Kathmandu, have so far found seven dead bodies, including two on Monday.

"There are no chances of finding survivors. Our focus is on recovering bodies," Bhesh Raj Rijal, a senior police official in Chitwan district said.

Family members, who gathered at the search site, have given up hope on finding their loved ones alive, an official said.

"They are requesting us to at least find the dead bodies. The scene here is grim," said Khimananda Bhusal, a government official in the district.

Landslides and floods triggered by torrential monsoon rains have killed over 100 people in Nepal since mid-June.

Following the landslide, the government announced plans to ban buses from travelling at night in places with adverse weather forecast.