Drone strike hits Yandex's largest data center in Kaluga, second attack in two days
A drone attack on the night of October 9 struck Yandex's largest data center in Kaluga, Russia, putting several modules out of operation and prompting the company to warn of possible service interruptions. It was the second attack on a Yandex facility in less than a day, following an October 8 strike on the company's data center in Sasovo, Ryazan Oblast. The Kaluga site, Yandex's most powerful facility, spans 130,000 square meters and has a design capacity of 63 MW.
Key points
- Yandex's data center in Kaluga was struck in a drone attack on the night of October 9, with several modules completely put out of operation.
- Yandex said there were no casualties at the Kaluga site and warned that some of its services may operate with interruptions.
- The Kaluga facility is Yandex's largest and most powerful data center in Russia, spanning 130,000 square meters with a total design capacity of 63 MW — roughly 5.2 times more powerful than the Sasovo site.
- Kaluga Oblast Governor Vladislav Shapsha said 26 drones were shot down over the region and nine people were injured; damage was recorded to municipal infrastructure and private houses in two municipal districts.
- It was the second attack on a Yandex data center in less than a day: on October 8 a drone strike hit the Sasovo, Ryazan Oblast facility, causing a fire and suspending operations.
- Yandex said it could not confirm the possibility of restoring equipment at the Sasovo site, which houses two of the company's three supercomputers used for neural network training.
- The earlier Sasovo fire disrupted Yandex Disk, Yandex Documents, Yandex Mail, and services from Avito, IVI, MegaFon, Russian Railways (RZhD), and T-Bank; the Ukrainian military has not commented on the Kaluga attack.
Why it matters
The Kaluga strike hits the heart of Yandex's domestic infrastructure: the facility provides the bulk of the company's cloud computing and services in Russia and is nearly 5.2 times more powerful than the Sasovo site struck the day before. Coming on top of the Sasovo fire, which already disrupted major Russian consumer and business services and may have damaged two of Yandex's three AI-training supercomputers, the cumulative impact on Russia's largest tech company is significant even if Yandex's redundant cloud architecture can redistribute some load. The Ukrainian military has not publicly claimed the strike.
What happened
A drone attack on the night of October 9 struck Yandex's data center in Kaluga, located in the Grabtsevo industrial park. Several modules were completely put out of operation, and Yandex warned that some of its services may run with interruptions. The company said there were no casualties at the facility and that emergency services and Yandex specialists were working on site, with the full scale of damage still being assessed.
It was the second attack on Yandex infrastructure in less than a day. On October 8, a drone strike hit the company's data center in Sasovo, Ryazan Oblast, causing a fire and suspending operations. Yandex later said it could not confirm the possibility of restoring equipment there. The Sasovo fire triggered disruptions to Yandex Disk, Yandex Documents, Yandex Mail, and to services operated by Avito, IVI, MegaFon, Russian Railways (RZhD), and T-Bank.
In Kaluga Oblast, Governor Vladislav Shapsha said 26 drones were shot down over the region and that nine people were injured. Damage to municipal infrastructure and private houses was reported in two municipal districts. The Ukrainian military did not comment on the attack at the time of reporting.
How Ukrainian sources describe it
All six source outlets covering the strike are Ukrainian, and they frame the Kaluga attack as a significant blow to Russian IT infrastructure. The reporting emphasizes the facility's status as Yandex's largest and most powerful data center and the operational impact — modules taken offline, services running with interruptions. Several outlets place the strike in the context of prior Russian mass attacks on Ukrainian data centers, including MiroHost, Parkovy, Data Group, UTELS, Pavutyna, and facilities operated by Kyivstar and Ukrtelecom, with the Parkovy data center reportedly ceasing operations entirely on October 1, 2026. Headlines stress both the scale of the facility hit and the reciprocity of attacks on data center infrastructure.
Background
Yandex operates five main data centers in Russia. Three — in Vladimir, Mytishchi, and Ivanteyevka — remained undamaged as of the latest reporting, while the Sasovo and Kaluga facilities have been hit. The company also maintains a data center in Mäntsälä, Finland, for international services. The Kaluga site, located in the Grabtsevo industrial park, spans 130,000 square meters with a total design capacity of 63 MW and is Yandex's largest and most powerful facility. Yandex's cloud infrastructure uses redundant data storage across four availability zones, which the company says can allow partial information recovery and load redistribution to other sites. The Sasovo site houses two of Yandex's three supercomputers used for neural network training.
According to cyberlaw expert Sarkis Darbinyan, Russia has nearly 200 data centers. He says damage to individual regional facilities could cause local disruptions in state systems, medical services, school electronic gradebooks, and online cash registers, but would not necessarily lead to a large-scale internet shutdown.
Between September 23 and 28, Russian strikes damaged at least six data centers in Ukraine, including MiroHost, Parkovy, Data Group, UTELS, and Pavutyna, as well as Kyivstar and Ukrtelecom facilities. The Parkovy data center reportedly ceased operations entirely on October 1, 2026.