Ukrainian drone strikes targeted Russia's major petrochemical hub of Nizhnekamsk on Sunday, damaging industrial facilities and injuring three people, while a separate attack killed an electrical substation worker in the southern city of Taganrog, according to Russian officials and media reports.
Nizhnekamsk Mayor Radmir Belyaev said the city, located in Russia's Tatarstan region, had come under a prolonged drone attack overnight.
"Early this morning, Nizhnekamsk was the target of a massive and prolonged attack by enemy drones. As a result of this attack, facilities in the industrial zone were damaged," Belyaev wrote on Telegram.
He said a residential building was also damaged.
Regional authorities reported three people injured in the attack, according to Russian media.
Ukrainian and Russian media reported that the strikes had sparked a fire at the Nizhnekamskneftekhim (NKNK) petrochemical complex, owned by Russian petrochemical company Sibur.
Videos circulating on social media showed flames and thick smoke rising above an industrial site, although AFP said it had not independently authenticated the footage.
Nizhnekamsk, home to approximately 240,000 people, is a major center of Russia's petrochemical industry, hosting oil refineries and large chemical production facilities.
Separately, an electrical substation engineer was killed in an overnight Ukrainian attack on Taganrog, an industrial port city in Russia's Rostov region near the Ukrainian border, regional Governor Yuri Slyusar said.
Taganrog Mayor Svetlana Kambulova said a fire at an electrical substation had been extinguished following the attack.
She added that authorities had declared a local state of emergency.
Russia's Defense Ministry said its air defenses had shot down 533 Ukrainian drones between Saturday night and Sunday morning.
According to the ministry, the interceptions took place across 12 Russian regions and Russian-annexed Crimea.
The reported number of intercepted drones could not be independently verified.
There was no immediate response from Kyiv regarding the latest attacks.
Ukraine has previously said it targets Russian industrial facilities in response to deadly Russian strikes against Ukrainian territory.