An expert in international law says the destruction of the huge dam in the Russian-controlled area of southern Ukraine amounts to war crimes.
A state of emergency has been declared and between 35 and 70 towns are expected to flood after the wall of water 11 metres high was unleased down the river.
Thousands of people are being evacuated over fears the flooding will be catastrophic.
Ukraine's military and NATO have accused Russia of blowing up the dam, while Russia has blamed Ukraine.
However University of Waikato Professor of Law Al Gillespie says it's quite simply a war crime.
