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You can investigate it, so we can be 200% sure that Nebok was the one who did it.
Sure, I'll link the evidence to Neb and also to Arandor!
Look, the very first phrase in Neb's profile, "I am not alive, and I don't regret it," belongs to Vasily Stus, a famous Ukrainian poet who was imprisoned and died in Perm-36, which is located in the Chusovskoy urban district of the Perm Krai (and you can get to Perm-36 from both links). The administrative center is the city of Perm, and its coat of arms looked like this until 1998: 
Well, theoretically, we see a cross here, even two of them, on the Bible, and instead of a sun, a bright red background, and... a bear? that is hugging... a tree?
To be honest, I initially had a different picture in mind for the cartridge casings.
If someone doesn't like the coat of arms of the city of Perm, you can look at the coat of arms of the Perm Krai.
The connection remains, but how to go from the evidence to Stus without knowing about him – I don't know. I followed the GM's path from the profile.