The attacks were reported by the Ukrainian monitoring Telegram channels Exilenova+ and Supernova+. ASTRA established that the fire broke out on the grounds of the Sasta machine-tool plant, where the Yandex DC data center is also located.
Yandex reported "power supply disruptions" in a separate availability zone of its Yandex Cloud platform. The company later confirmed to RBC that an "incident that affected part of the infrastructure" had occurred at the data center in Sasovo.
"The situation at the site is now under control, there are no casualties. The team is eliminating the consequences of the incident and restoring the operation of the affected services," Yandex said.
After the attack, some Yandex services malfunctioned. TV Rain noted that several other Runet sites also became unavailable, including the autoposting platform Postmypost and the regional edition of Komsomolskaya Pravda.
ASTRA, which examined footage of the fire in Bashkortostan, also concluded that the fire most likely occurred on the grounds of the Gazprom Neftekhim Salavat refinery, one of Russia's largest oil refining and petrochemical complexes. The plant, which has repeatedly come under Ukrainian attack and suspended operations afterward, is located roughly 1,400 kilometers from the border with Ukraine. Exilenova+, citing local residents, also reported explosions in Sterlitamak.
An air alert was declared in Bashkortostan overnight because of the threat of a Ukrainian drone attack. Local authorities did not report on the consequences of the attack.
The Russian Defense Ministry said 399 Ukrainian drones were shot down over the territories of the Belgorod, Bryansk, Volgograd, Voronezh, Kursk, Lipetsk, Oryol, Orenburg, Penza, Rostov, Ryazan, Samara, Saratov, Smolensk, Tambov, Tula and Ulyanovsk regions, the Moscow region, Bashkortostan, annexed Crimea, Tatarstan and over the waters of the Black Sea.