Ukraine has said that three of its air force pilots, including a renowned fighter jet pilot with the call-sign "Juice", were killed in a mid-air collision yesterday.
The crash marks a major upset for Kyiv, which has been looking to secure advanced F-16 jets to strengthen its Soviet-era air force and push ahead with its counteroffensive.
"We express our condolences to the families of the victims. This is a painful and irreparable loss for all of us," Ukraine's air force said, calling the crash "terrible".
The crash took place in Ukraine's northern Zhytomyr region and involved two L-39 combat training aircraft, it said, adding an investigation was under way.
Air force spokesperson Yuriy Ignat said one of the pilots killed - Andrii Pilshchykov - who went by the call-sign "Juice", was a young officer with "mega knowledge and mega talent".
"Major Andrii Pilshchykov devoted his short but very bright life to combat aviation, he dreamed of F-16s in the Ukrainian sky," he said in a tribute shared on social media.
"You were more than a friend. Rest in peace, you have done so much for us," he added.
Russia downs Ukrainian drones near Moscow
Russia reported a new drone attack on Moscow in the early hours of this morning, which again forced authorities to temporarily shut down all three major airports serving the capital.
Moscow Mayor Sergei Sobyanin said that a drone was brought down by air defence systems over the Istra district of the Moscow region. The district is some 50km west of the Kremlin.
Three major Moscow airports, Sheremetyevo, Domodedovo and Vnukovo, suspended flights for couple of hours, Russia's TASS news agency reported.
Aerial attacks on Moscow and other Russian-held territory have intensified in recent weeks, including 42 drones intercepted over the Russia-held Crimean Peninsula on Friday - one of the biggest reported air assaults since the war began.
Although the attacks have not caused extensive damage, their intensity has forced the Russian authorities to temporarily shut down airports serving the capital several times this week.
Russia has blamed Ukraine for the attack and all the previous assaults that intensified after two drones were destroyed over the Kremlin in early May.
Ukraine did not immediately comment and almost never publicly claims responsibility for attacks inside Russia or on Russian-controlled territory in Ukraine.
The Ukrainian military has said previously, however, that destroying Russia's military infrastructure helps a counteroffensive that Ukraine began in June
Ukraine's GUR military intelligence agency had said a Ukrainian drone attack had hit a Russian military base deep inside annexed Crimea, while residents reported casualties, explosions and a road closure.
Ukrainian intelligence officials said the attack struck Russia's 126th Coastal Defence Brigade based in Perevalnoye, a town more than 200km from Ukraine-controlled territory.
"We confirm that there was a hit," said GUR spokesman Andriy Yusoy.
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Moscow annexed Ukraine's Crimea in 2014, declaring it Russian territory. The United States says it supports Ukrainian attacks on Russian military targets on the Black Sea peninsula because it should be demilitarised.
"People - not only on the Ukrainian mainland but also in Crimea - need to remember and believe that our victory and their liberation are not far away," Ukraine's military intelligence chief Kyrylo Budanov said of Friday's strike.
Perevalnoye residents, posting on the Telegram messaging app, reported hearing blasts from the military base and cited casualties.
"Two people died on a firing range, one was taken to a hospital in a severe condition. This is information from above, from the firing range," said a user nicknamed Abdul Has, whose profile picture shows a man in camouflaged uniform.
"Why was a gate to the military town closed?" another asked.
Another resident with the call sign Lis asked others not to disclose information.
"Residents of Perevalnoye, I strongly recommend - don't write here what happened and how," Lis wrote. "We help them to direct fire in the future with that."
