Ukraine and Russia continue to blame each other for the destruction of a hydroelectric power-generating dam on the Dnipro River in Ukraine.
Ukraine's military announced on Tuesday that the Kakhovka dam on the Dnipro River in the southern region of Kherson has been destroyed by Russians.
A local governor says efforts are underway to evacuate the roughly 16,000 residents being exposed to the danger of flooding.
In a video message released on Wednesday, Ukrainian President Volodymyr Zelenskyy denounced Russia. He said, "The Russian occupiers have committed the biggest crime of ecocide on the Ukrainian land."
He also said at least tens of thousands of people remain in the flood zone.
But Kremlin spokesman Dmitry Peskov blamed Ukraine for the destruction, calling it "a deliberate act of sabotage by the Ukrainian side." He added that Ukraine is also aiming to deprive Russian-annexed Crimea of the freshwater it receives from the dam.
White House National Security Council spokesperson John Kirby told reporters on Tuesday that he cannot say conclusively what happened at this point.
He added that the US government is working with the Ukrainians to gather more information.
The United Nations Security Council convened an emergency session on Tuesday to discuss the incident.
UN Under-Secretary-General for Humanitarian Affairs and Emergency Relief Coordinator Martin Griffiths said the situation may represent the "most significant" damage to civilian infrastructure since the war in Ukraine began in February last year.