Flooding caused by the destruction of Ukraine's Kakhovka dam will have a "catastrophic effect" on efforts to find landmines in the region, the International Committee of the Red Cross has said.
Erik Tollefsen, head of the Weapon Contamination Unit at the ICRC, said "massive numbers" of mines have been laid, and many could now be “somewhere downstream”.
"We knew where the hazards were," he said. "Now we don't know. All we know is that they are somewhere downstream.
"This is a major concern because it will affect not just the population, but also all of those that are coming in to help," he said.
The ICRC said the floodwaters would not damage or deactivate the explosive devices, which means they could pose a threat for decades to come.
Mine clearing 'will almost certainly take longer'
Jasmine Dann, operations manager for Halo, a British-based charity which clears landmines and other explosives, told The National it discovered around 5,000 mines in the Mykolaiv oblast in the last month alone - around 460 of which were found near the riverbanks.
But the charity has now had to suspend its work due to the flooding.
She said anti-tank mines were laid at the lowest points of the Inhulets River to prevent troops from crossing in vehicles until Mykolaiv was liberated in November 2022.
"These mines are now posing a fatal risk to civilians who are returning to their homes or use the fertile banks to graze their animals, cultivate crops and fish," she said in a statement.
"Our demining teams regularly cross the river to access minefields, but three of these are now underwater and we’ve had to suspend work on others nearby."
She added: "Whether the mines are dislodged or not, clearing them will almost certainly take longer now."
Ukraine's Kakhovka dam in Russian-held territory was destroyed on Tuesday, flooding dozens of villages and parts of a nearby city and sparking fears of a humanitarian disaster.
Flooding from the Kakhovka dam breach extends over 600 square kilometres on the Ukrainian-held right bank of the Dnipro river and the Russian-held left bank, the region's governor said on Thursday.
"The average level of flooding is 5.61 metres. Six hundred square kilometres of the Kherson region are under water, of which 32 per cent is the right bank and 68 per cent is the left bank," Oleksandr Prokudin, governor of the Kherson region, said on social media.
Downstream from the dam in the Kherson region, there were "a lot of what we call defensive minefields put up by parties to the conflict", said Norwegian specialist Mr Tollefsen.
Normally, these are "very, very populated with both anti-personnel mines and anti-vehicle mines", he added.
The ICRC does not know how many mines might have been submerged or washed away by the floodwaters.
"The parties to conflict haven't declared any kind of numbers of mines that have been laid," Mr Tollefsen said.
"We just know that the numbers are massive."
The ICRC had spent several months helping mine-clearance operations in Ukraine, mapping and marking minefields and providing training and equipment, Mr Tollefsen said.
"Now all of that has been washed away."
Anti-personnel and anti-tank mines such as the TM-57 will now have been dispersed into unknown locations, he said.
Nataliya Humeniuk, a spokeswoman for Ukraine's military South Command, told Ukrainian TV: "Many anti-infantry mines [in Russian-seized areas] have been dislodged, becoming floating mines.
"They pose a great danger," she said, explaining that they were likely to explode if they collided or hit debris.
This week the ICRC presented a new drone that uses artificial intelligence to locate mines and other explosive remnants of war from the heat they emit. It could one day be used in Ukraine.
The new drone can cover in a day the same surface area a demining dog would in six months but has so far been used only in testing in Jordan.
The Geneva-based ICRC hopes to use it for the first time this year around the city of Aleppo in north-west Syria.
It will not remove mines itself but should accelerate their detection thanks to its cameras, heat detector and artificial intelligence software, which the ICRC intends to share.
Help 'slow to arrive'
Moscow and Kyiv have blamed each other for the destruction of the 1950s Soviet-era dam on the Dnipro river.
The flooding has forced several thousand civilians to leave their homes.
On Wednesday in an interview with Germany's Bild daily, Ukrainian President Volodymyr Zelenskyy expressed dismay at a lack of help from the UN and Red Cross with the fall-out from the destruction of the dam.
Flooding in Ukraine following dam destruction - in pictures
"They are not there," Mr Zelenskyy said, adding that he was "in shock because I think they are the forces who have to be there to save people's lives".
The UN's humanitarian affairs office said a team was in Kherson to coordinate relief efforts. Access to drinking water was a major concern and around 12,000 bottles of water and 10,000 purification tablets had been distributed so far.
France also said it will send aid to Ukraine.
Around 4,000 people have reportedly been evacuated from both the Russian and Ukrainian-controlled sides of the river, according to officials, although some people living in Moscow-controlled areas have complained help has been slow to arrive.
In the Moscow-controlled city of Oleshky, Lera, 19, told The Associated Press the first floor of her home was flooded.
“Everything around us is floating. People are standing on rooftops and asking for help, but no one is evacuating them,” said Lera, who declined to give her last name for fear of reprisals.
Most Russian troops fled Oleshky shortly after the dam incident, Lera said, although a military checkpoint remains, and boats with people trying to leave have come under fire from soldiers. Her claim could not be independently verified.
On Wednesday, Mr Zelenskyy met with officials on how to provide drinking water to residents in Ukrainian-held areas, as well as assess damage to wetlands, farms and other property from what he called “a crime of ecocide" and "a man-made strike on the environment, after which nature will have to recover for decades.”
He said he had shared intelligence with Ukraine's international partners a year ago showing there was a risk of the dam being targeted.
"We shared this information with our partners and all of them said yes, the risk is very high that the dam is going to be blown up," he said.
Nato Secretary General Jens Stoltenberg said he will chair a meeting on Thursday of an emergency co-ordination panel with Ukraine on the "outrageous destruction" of the dam.
The dam supplied water to the Zaporizhzhia nuclear plant and Crimea, which was annexed by Russia in 2014.
The United Nations nuclear chief Rafael Grossi said on Thursday that the watchdog intends to rotate inspectors at the Russian-held Zaporizhzhia nuclear plant next week, but that plans must be agreed with Russian and Ukrainian authorities, Russian state-owned news agency RIA reported.
Ukraine has been rapidly integrating combat jets sent from Eastern Europe to provide secure air power before launching a major counter-offensive, according to military sources.
Kyiv’s armoured brigades are now probing for a weakness in the Russian front line before striking, potentially next week, analysts said.
The latest satellite imagery and geolocated intelligence suggests Ukraine’s main incursions are occurring south of Donetsk and around the besieged town of Bakhmut.