Thousands of people are believed to be trapped by floodwaters spread across a swath of Ukraine after a catastrophic dam collapse.

The collapse of the Kakhovka hydroelectric dam and emptying of its reservoir on the Dnieper River added to the misery the region has suffered for more than a year from artillery and missile attacks.

Russian and Ukrainian officials used terms like ‘ecological disaster’ and ‘terrorist act’ to describe the torrent of water gushing through the broken dam and beginning to empty an upstream reservoir that is one of the world’s largest.

Ukrainian forces are making a major effort to punch through Russian defensive lines in southeast Ukraine for a second day.

In Ukraine, the army’s commander said air defenses shot down more than 30 missiles and drones in a new round of Russian air attacks overnight.