On Monday, Russia blamed Ukraine for explosions at two air bases home to strategic bombers.
The attacks were carried out with "Soviet-era" drones, per Russia's Ministry of Defense.
If true, that is a "baffling" admission, military expert Samuel Bendett told Insider.
Russia's story in the wake of mysterious explosions at two air bases acknowledges an embarrassing weakness in its ability to defend its military installations.
It argued that drones first flown before the fall of the Soviet Union hit two airfields hundreds of miles from Ukraine, inflicting casualties on Russian forces and damaging aircraft in a brazen act of revenge for the Kremlin's attacks on civilian infrastructure.
"Baffling," Samuel Bendett, a military expert with the Center for Naval Analysis, a Washington think tank, said in an interview. "Why didn't Russian air defenses track and identify the targets so deep inside the country?"
In a statement on Monday, the Russian Ministry of Defense asserted that attacks were carried out on its Engels and Dyagilevo air bases - each home to nuclear-capable strategic bombers - far from the front lines in Ukraine, killing three soldiers and damaging some aircraft. Those attacks, it claimed, were carried out with "Soviet-era" unmanned aerial vehicles.
Russia has played fast and loose with facts throughout the war in Ukraine, but its statement of blame on Monday does not make its own military look particularly competent.
Some observers believe the Russian defense ministry may have been referencing the Tu-141 reconnaissance drone that was first built in the 1970s. In March, one of these drones, armed with a bomb, crashed in Croatia. Neither Ukraine nor Russia claimed it was theirs, but the incident showed the craft is still being used today.
"It's less of a UAV than a flying missile, basically. It's not sophisticated. And it does probably make a lot of noise when it flies," Bendett said of the Tu-141 during an interview with Insider. "Again, it's one thing to strike something within, let's say, a hundred to 200 kilometers from the border. It's a different problem set to strike something 600 kilometers away."
Ukraine has not claimed responsibility for the attack. It is possible that Russia's frank acknowledgement of vulnerability is cover for another, arguably more embarrassing possibility: that the strikes were carried out by Ukrainian agents within Russia, speculation that Bendett noted was being raised by war-watchers on Telegram.
Mykhaylo Podolyak, an advisor to President Volodymyr Zelenskyy, suggested it was payback for Russia's ongoing attacks on Ukraine's energy infrastructure, which has caused power outages in the capital, Kyiv, writing on social media that "if something is launched into other countries' airspace, sooner or later unknown flying objects will return to departure point."
The lastest incidents are not the first time Russian territory has apparently been struck at range. In June, Russia state media blamed "terrorist actions" - and two "unmanned aerial vehicles" - for an attack on the Novoshakhtinsk oil refinery, causing a fire but no reported injuries.
But that attack was just five miles from the Ukraine-Russia border. Monday's incidents, if they were indeed carried out by aircraft launched from Ukraine, could indicate Kyiv has the ability to carry out strikes well within the target-rich environment of the Russian interior - a possibility for which the Kremlin does not seem prepared.
One day's attacks are not likely to change the overall trajectory of the war that Russia launched in February when it invaded Ukraine. But, as with Ukraine's November attack on Russia's Black Sea Fleet using naval drones, they have the potential to inflict a psychological cost and forces Russia to expend resources protecting assets it did not previously believe needed much of a defense.
"We don't know if it was in fact a drone. We don't know if it was that Tu-141. But it was something," Bendett said, "and it definitely was effective."
Justin Bronk, a senior research fellow at the Royal United Services Institute, a British think tank, concurred, telling Insider that the attack's impact was bigger than the day's losses.
"I think it's fair to say that the symbolic nature of the attack and the potential diversion of defensive systems to protect Engels and the other bomber bases is of greater significance than the physical damage inflicted on Russian Long Range Aviation - which has been one of the more effective parts of the Russian military throughout this war," he said.
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