Ukrainian troops attempted to cross the Psyol River in Sumy Region using armored vehicles, Russian security officials told RIA Novosti.

According to the agency’s source, the incident took place near the settlement of Zapselye. An assault group from the 21st Separate Mechanized Brigade of the Armed Forces of Ukraine, operating with FPV drone support, tried to move across the river.

The crossing failed, the source said. Several Ukrainian servicemen reportedly drowned, while the rest of the group withdrew.

The episode came after Russia’s Defense Ministry said on May 10 that units of the Sever group of forces had repelled enemy attacks, destroying up to 80 Ukrainian servicemen, a multiple-launch rocket system and two Ukrainian surface-to-air missile systems.

The ministry said retaliatory strikes hit Ukrainian personnel and equipment from two mechanized brigades near Andreyevka and Malaya Korchakovka in Sumy Region. Russian forces also struck units from Ukrainian mechanized and motorized infantry brigades, as well as a territorial defense brigade, in Kharkov Region.

Russia’s Defense Ministry also reported 16,071 ceasefire violations by the Ukrainian side in the special military operation zone. It said Russian troops responded to the violations in kind.