KYIV/MOSCOW - Ukraine and Russia on Monday carried out the first stage of a prisoner exchange following agreements reached in Istanbul last week, Ukraine's Coordinating Headquarters for the Treatment of Prisoners of War reported.

The Russian Defense Ministry said in a statement that "the first group of Russian servicemen under the age of 25 was returned from the territory controlled by the Kyiv regime."

A similar number of prisoners of war from the Ukrainian army were also transferred, it added.

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During their last round of talks in Istanbul on June 2, Russia and Ukraine agreed on an "all-for-all" exchange involving seriously ill and wounded prisoners, as well as soldiers under the age of 25, according to Russian Presidential Aide Vladimir Medinsky.

Efforts remain ongoing to repatriate the bodies of Ukrainian servicemen, the Ukrainian agency said.

Drone attacks

Meanwhile, Russia's air defense systems intercepted and destroyed 102 Ukrainian fixed-wing unmanned aerial vehicles overnight, the country's Ministry of Defense said Tuesday via its official Telegram channel.

According to the ministry, the drones were neutralized between 9:50 pm Moscow time (1850 GMT) on Monday and 5:50 am (0250 GMT) on Tuesday, across several regions in western and central Russia.

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Forty-six unmanned vehicles were downed over Bryansk Oblast, 20 over Belgorod Oblast, nine each over Voronezh Oblast and Crimea, four each over Kaluga Oblast and the Republic of Tatarstan, three over Moscow Oblast, two each over Leningrad, Oryol, and Kursk Oblasts, and one over Smolensk Oblast, said the ministry.