Ukraine hailed the return Saturday of 45 Azov battalion fighters captured during the battle for Mariupol last year while Russia said three of its pilots had been released by Kyiv. The exact details of the apparent prisoner swap remained unclear.

A video and still photographs, released Saturday (May 6) by the Coordination Headquarters for the Treatment of Prisoners of War on the telegram app showed what is said to be Ukrainian POWs after the swap.

The freed Ukrainian prisoners included 42 men and three women from the Azov battalion, said Andriy Yermak, the head of President Volodymyr Zelenskyy's office. The Azov unit, which did much of the fighting in the failed defense of the port city of Mariupol, has been lionized as heroes by many Ukrainians but is widely vilified in Russia.

The Russian Defense Ministry said in a statement that three pilots had been returned and were being provided with medical and psychological assistance.

Moscow and Kyiv have undertaken regular prisoner exchanges since Russia's full-scale invasion in February last year.

Russia says it launched its "special military operation" to counter a threat from Kyiv's relations with the West, while Ukraine and its Western partners say it was an unprovoked land grab.