More bodies were recovered on Monday after floods devasted two villages - Bushushu and Nyamukubi - in the Kalehe territory of the country.

It comes days after torrential rain, which began on Thursday, triggered landslides and caused rivers to break their banks.

Local civil society sources said the recovered bodies were wrapped in bags and piled into mass graves over the weekend.

On Friday, it was reported that at least 176 people had been killed, as humanitarian workers dug through the remains of the flattened villages to recover mud-caked bodies from the debris with hundreds of people still missing.

But according to the latest reports, that number has now more than doubled.

'The worst flood'

Speaking to the Reuters news agency, South Kivu governor Theo Ngwabidje Kasi said the death roll now stood at 401, but he did not provide further details.

"It is the worst flood we have ever had," civil society representative Christian Zihindula Bazibuhe said, adding that bodies were still floating on Lake Kivu.

The Congolese government declared Monday as a national day of mourning, with flags to fly at half-staff in memory of the victims.

According to a government spokesperson, a delegation of government officials and lawmakers sent by Congo's president, Felix Tshisekedi, arrived in Bukavu - a city near the southern part of Lake Kivu - and planned to visit the devastated area on the same day.

'The whole village has been turned into a wasteland'

On Sunday, a grieving survivor said she lost her family and many neighbours.

Anuarite Zikujuwa said: "The whole village has been turned into a wasteland.

"There's only stones left, and we can't even tell where our land once was."

The United Nations' humanitarian agency OCHA also added that around 3,000 families lost their homes due to the floods.

United Nations (UN) climate experts have warned that rising temperatures increase the intensity and frequency of rains across Africa.

UN secretary-general Antonio Guterres described the floods as "another illustration of the acceleration of climate change" and the impact on nations "that have contributed nothing to global warming".

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Last year, at least over 100 people were killed after devastating floods hit Kinshasa.

At the time, the United Nations Office for the Coordination of Humanitarian Affairs (OCHA) said: "At least 169 people died after heavy rains hit Kinshasa during the night of 12-13 December, according to authorities."

The devastating floods in Congo - in pictures