New video and analysis of drone and satellite imagery show that the Russians may have lost as many as 70 armored vehicles and other equipment in attempting to cross the river early this week. Their goal was to try to encircle Ukrainian defenses in the Luhansk region, but it failed spectacularly.

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In its account of the battle, Ukraine's 80th separate assault brigade said it had "destroyed the pontoons and thwarted nine crossing attempts."

It claimed that "at least 73 units of equipment were destroyed, including T-72 tanks" and a variety of infantry fighting vehicles.

This tally appears supported by analysis of drone video showing Russian equipment strewn along a track to the north of the river, as well as half-submerged tanks.

It's clear that the Ukrainians had previously worked out where the Russians were likely to try to lay down the pontoons and had observed the approach of Russian units. Reconnaissance of possible crossing points had begun at least two days before the Russian attempt.

The Siverskyi Donets flows quickly and the Russians appear to have needed motorized tugs to try to complete the bridge. The noise was a further clue to Ukrainian units that an attempt to ford the river was underway.