Мафия 65. S1-ut system: criminal scum strikes back!

six-digit coordinates of the polar circles.
And 14/12/11 - someone's death that reached the pole.

Regarding the six-digit coordinates, the investigator explained it clearly. You can choose any point on the map, and it will have six-digit coordinates.
Regarding the death of Academician Boris Chertok, it was about Leon, who was killed.
There was also something about an expedition to Alexigla, but there's no exact date there, only the century since the day the expedition reached the pole - December 14, 1911.
But Alex is acting suspiciously; if you remember the first day, he completely ignored that clue about the polar circle. And when many people thought that Tactical was the killer, and the clues might point to Tactical, it seemed to suit him. Although he wasn't the one.

Added 6 minutes later
Arandor, Neyra could have been wrong; Tactical doesn't have any information except for posts in the thread. Vespers also defended him, and she turned out to be innocent.