It sounds like it was the bomber, Serhiy Batryn, that was reported as dead. Conflicting reports as to whether he has actually died. This was not related to Russia from what I could gather. He had a long standing feud with members of the local council.
I can’t help but think that’s why Putin invaded Ukraine. He needed something to keep the masses distracted. He’s afraid that he’ll get assassinated if he ever leaves power, whether voluntarily or by violent overthrow.