Ukraine's navy and military intelligence carried out a "special operation" overnight in which units landed on Russian-occupied Crimea, the defense ministry's Main Directorate of Intelligence (HUR) said Thursday.

The operation, which Reuters was unable to independently confirm, would amount to a rare demonstration that Ukrainian forces are able to stage ground operations in Crimea, which Russia seized and annexed in 2014.

Brief and dark video footage posted alongside the statement showed a small motorboat moving through water at night near a coastline. HUR said the landing point was on the western tip of Crimea, near the settlements of Olenivka and Mayak.

"Special units on watercraft landed on the shore in the area of the Olenivka and Mayak settlements," HUR said in a statement.

It said "all goals" had been achieved and casualties inflicted on the enemy, but did not identify the goals.

"Also, the state flag flew again in Ukrainian Crimea," it said, without saying where exactly or providing further details.

Russia did not comment on the report, which coincided with Ukraine's Independence Day.

Ukrainian President Volodymyr Zelenskyy vowed on Wednesday to end Russia's occupation of Crimea although Russia shows no sign of abandoning the peninsula.

On Wednesday, Ukraine's military intelligence also reported deliberately luring a Russian military pilot to land his Mi-8 helicopter at a Ukrainian airfield.