Russian Foreign Ministry spokeswoman Maria Zakharova has said in a statement: "The Kyiv regime is continuing its terrorist activity with the sole purpose of intimidating the peaceful population of Russia."
Russian officials have vowed a "tough response" to Ukraine's latest reported attacks on several regions in the country, in addition to the Moscow-controlled part of Ukraine's eastern Donetsk region, BBC reports.
Russian Foreign Ministry spokeswoman Maria Zakharova has said in a statement: "The Kyiv regime is continuing its terrorist activity with the sole purpose of intimidating the peaceful population of Russia."
She adds that Ukraine "understands perfectly well" that the recent attacks "make no sense from a military point of view".
The Russian spokeswoman mentioned several attacks in the past 24 hours, including what she said was a "massive" overnight strike on the regional capital Kursk.
Earlier, the local governor for Kursk said 13 people had been injured when the wreckage of a Ukrainian missile fell on the multi-storey building in the city.
Ukrainian President Volodymyr Zelensky earlier confirmed that Ukrainian troops were now engaged in fighting within Russian jurisdiction.
The exact locations and scope of the operations remain unclear, but Zelensky's confirmation suggests a significant expansion of Ukraine's military efforts.
The President was quoted by CNN as saying: “Ukraine is proving that it really knows how to restore justice and guarantees exactly the kind of pressure that is needed – pressure on the aggressor.”
He also thanked “every unit” of Ukraine’s armed forces for making it possible “to push the war out into the aggressor’s territory.”
This is the first time Zelensky officially acknowledged the incursion, which took by surprise both Russia and Ukraine’s allies. Ukrainian officials have for days remained tight-lipped about the operation, even as photographs, videos and firsthand reports of Ukrainian soldiers inside Russia started to emerge.