According to a local official, the death toll in eastern Congo from flooding has nearly doubled to close to 400 as of Sunday.

The administrator of South Kivu’s Kalehe territory, which is the area most affected, told The Associated Press over the phone that many more bodies had been recovered on Sunday, some of them floating in Lake Kivu.

Thomas Bakenge, the administrator of the site, said that the number of confirmed dead was 394. However, this was only a preliminary count as the search continues. Local groups reported that more than 300 victims were buried by Sunday.

On Thursday evening, torrential rains began to fall across the Kalehe region. The rivers broke their banks and flash floods washed away most of the buildings in Bushushu, Nyamukubi villages, causing a large number of deaths.

Delphin Birimbi is a civic leader from Kalehe. He said that he was aware of the fact that thousands were still missing. He told the AP some doctors had arrived to treat the wounded, but the communities were pleading more for emergency assistance.

Aid efforts were hindered by the destruction caused by flooding, as two main roads were impassable.

Valet Chebujongo said that more than 170 victims had been buried in four graves. Valet is a young activist who has helped in the rescue effort in Kalehe. Chebujongo told reporters that he could not imagine burying victims in mass graves without coffins.

The Congolese Government declared Monday a day of national mourning. Flags will be flown at half-staff to honor the victims.

According to a spokesperson for the government, a delegation of government officials, lawmakers, and other representatives sent by Congo’s President, Felix Tshisekedi arrived in Bukavu. The city is located near the southern end of Lake Kivu. They plan to visit the area devastated on Monday.

In East Africa, heavy rains have caused misery for thousands of people in the past few days. This includes parts of Uganda and Kenya.

In Rwanda, a country that borders Congo, 129 people were killed earlier this week by flooding and landslides.