The breach of a large dam in southern Ukraine will have a catastrophic effect on the location of landmines, the Red Cross has warned.
Thousands of people have already been evacuated from parts of the Kherson region as water continues to flow down the Dnieper River, which separates territory controlled by Russia and Ukraine.
Both Ukraine and Russia blame each other for the sabotage of the Kakhovka Dam.
Three flood-related deaths were reported in Russian-held Oleshki.
Evgeny Rishchuk, the exiled Ukrainian mayor of the city, told Suspilne public television that he believed there would be more victims.
The BBC was unable to verify the claims of Ukrainian and Russian officials.
Erik Tollefsen, head of the Red Cross’ weapons contamination unit, warned that the discarded mines had caused great concern not only for the residents of Kherson, but also for those who came to help.
“We knew where the dangers were,” he told AFP. “We don’t know now.
“All we know is that they are somewhere downstream.
Natalya Khumeniuk, a spokeswoman for Ukraine’s Southern Military Command, told Ukrainian TV: “Many anti-personnel mines (in Russian-held areas) were thrown out, turning into floating mines.
“They pose a great danger,” she said, explaining that they are likely to explode if they collide or hit debris.
Local residents have tried to rescue pets and livestock from the flooded areas
The dam in Russian-controlled Nova Kakhovka was breached in the early hours of Tuesday, prompting mass evacuations as water levels downstream rose rapidly.
Authorities say 30 towns and villages along the river have been flooded and nearly 2,000 homes submerged in the city of Kherson, the capital of the Ukrainian-controlled region.
A woman who arrived in Kherson by rescue boat from the Russian-occupied east side of the river explained how quickly the situation escalated after learning of the disaster early Tuesday.
“We managed to collect our things but the water continued to rise. At that moment I was cooking buckwheat and my feet were already under water. It started to flood very quickly,” 40-year-old Katerina Krupić told the BBC.
“It feels like we’ve lived a lifetime in just one day.”
Interior Minister Igor Klymenko said the Ukrainians are developing a plan to help people on both sides of the Dnieper River.
“We are rescuing everyone on the right (Ukrainian-controlled) bank and developing a plan to help people on the left (Russian-controlled) bank.”
Of the 30 flooded towns and villages, 20 were controlled by Ukraine and 10 were temporarily occupied by Russia, he said.
Mr Klimenko also accused the Russians of leaving “people to fend for themselves”.
Rising water levels were expected to peak in Kherson late on Wednesday, but authorities fear a catastrophic impact on agriculture as the huge Kakhovka reservoir – upstream of the dam – flows into the Black Sea.
Kherson regional head Alexander Prokudin said 1,700 people had been evacuated so far, while Kremlin officials across the river said 1,200 people had been taken to safety.
Officials say more than 40,000 people – 17,000 in Ukrainian-controlled territory west of the Dnieper and 25,000 in the Russian-occupied east – must leave.
Unicef’s Damien Rance said the charity had seen homes completely destroyed as fears continued of trapped residents.
“Safe water has been affected in many of these locations as the water supply is apparently coming from the reservoir there as well as the electricity supply which has been interrupted.”
Police, state emergency services and charity workers evacuate people after dam burst
President Volodymyr Zelensky said earlier on Wednesday that hundreds of thousands of people in the Kherson region were without drinking water.
Both sides blame each other for the destruction of the dam.
Ukraine claims it has been mined by Russian forces and accuses Russia of doing little to help people in flooded areas on the Russian-occupied east bank of the river.
Democratic US Senator Bob Menendez, who chairs the upper house’s powerful foreign affairs committee, told the BBC he was “still not sure” that Russia was responsible for blowing up the dam.
“But again, the Russians have denied any actions they took against critical infrastructure in Ukraine — and those actions we know were taken by Russia,” he added.
Russia claimed the damage was caused by Ukrainian shelling and President Vladimir Putin called it a “barbaric act” in a phone call with Turkish leader Recep Tayyip Erdogan.
This is only the latest difficulty that befell the city of Kherson. It was occupied by Russian forces soon after the war began last year, but was liberated by Ukraine in November. Since then, the city has been bombarded by shelling.
Victoria Eremenko, 57, told the BBC her house was destroyed in February and she moved into her son’s flat, which is now flooded.
“We managed to get away,” she said. “There was panic, we had to go quickly and get the dogs. My brother is also semi-paralysed.”
In recent years, the Kakhovka Dam has become a symbol of leverage between Kyiv and Moscow.
When Russia illegally annexed Crimea in 2014, Kiev closed the dam and cut off Ukraine’s southern peninsula from a major water supply.