The Russian military is striking Sumy Oblast because of Ukraine's successes in Russia's Kursk Oblast, Vadym Mysnyk, a spokesperson for the Ukrainian military's Operational Tactical Group Siversk, told Radio Free Europe/Radio Liberty (RFE/RL) on Sept. 17.
The statement came after Russia launched a heavy drone attack on the northeastern Ukrainian region, disrupting electricity and water supplies.
Russian attacks against Sumy Oblast have escalated since Kyiv launched a cross-border incursion into the neighboring Kursk Oblast in early August.
Mysnyk nevertheless said that Russian strikes on Sumy Oblast would have continued even if Ukraine had not successfully advanced in the Kursk sector. While Russia has ramped up attacks against the region since August, Sumy Oblast has been shelled on a daily basis since the beginning of the full-scale invasion in 2022.
"It's just a matter of time before they dump all this (all the weapons) on us. Either here (in Sumy Oblast) or in another city. But they will strike at Ukraine with everything they have, using the entire arsenal," the spokesperson said.
"They (Russia) see our successes in the Kursk operation – and we are close to them – so there is probably some fear that we will somehow operate in other cities on the border," he added.
Mysnyk also noted that the Russian military had reduced the number of mortar attacks on the border of Sumy Oblast and stopped attacking Kharkiv Oblast with aerial guided bombs. This may indicate that Russia's resources are "not unlimited," he added.
Russia recently launched a counterattack in Kursk Oblast, seeking to dislodge Ukrainian troops from its soil. President Volodymyr Zelensky said that "everything was going according to our plan" and that the Russian "rapid" offensive had not yet achieved "serious" success in the area.
Ukrainian soldiers also have reportedly taken over 600 Russian captives and inflicted 6,000 casualties in Kursk Oblast as of early September.