At least seven people are missing after waters from the destroyed Nova Kakhovka dam flooded nearby areas, Russia’s TASS news agency cited the Moscow-installed mayor of the city of Nova Kakhovka as saying on Wednesday.

The Moscow-controlled Nova Kakhvovka dam on the Dnipro River was destroyed on Tuesday, flooding a swathe of the frontline in the Kherson region, forcing villagers to flee. Ukraine and Russia have blamed each other for the dam collapse.

About 42,000 people were at risk from flooding in Russian and Ukrainian controlled areas along the Dnipro River, said Ukrainian officials, as the United Nations aid chief warned of “grave and far-reaching consequences.”

“Of seven people we know for sure (are missing),” TASS cited Nova Kakhvovka mayor Vladimir Leontiev as saying. More than 900 people were evacuated on Tuesday from the Russian-controlled city of some 45,000 people, which sits on the left bank of the Dnipro River.

Ukrainian officials said that some 80 communities in the overall Kherson region are at risk of being flooded.

The governor of Ukraine’s Kherson region, Oleksandr Prokudin, said on Wednesday that 1,582 houses have been flooded on the right bank of the Dnipro River and some 1,457 people have been evacuated overnight.

Earlier, Prokudin also said that one civilian person was killed and one injured over the past day as a result of Russia’s shelling on the region and the city of Kherson itself.