Bernhard Fraktur Fett  Suggested by donshottype 
Ludlow Wartburg Fraktur  Suggested by donshottype 

Based on the style of _o_ I would call these soft blackletter letters a fraktur.
The Roman style _k_, the recognizable _x_ and the use of a short rather than long _s_ in the middle of a word suggests that it might be a modern design.
It would be helpful if you could mention where you found the letters.
Are they a logo?

No no, they aren't a logo.
Now i update the pic with 2 more options.
Error Design! use this blackletter a lot and i really like it.
Here is a bit bigger, look the Overload text.
https://www.instagram.com/p/BEIZLbTP7vm/

And here on the Torche text.
https://www.instagram.com/p/vmAGo6v7kg/?taken-by=errordesign

Sorry for my english, sucks a lot hahaha.

EDITED:
The additional specimens by the the poster makers at Error! Design http://error-design.com/v7/?page_id=30 are helpful
They show most of the lowercase and five capital letters.

Perhaps a variation of Bernhard Fraktur fett by Lucian Bernhard for Flinsch foundry, 1912-1922

Source: Klingspor Museum
AFAIK no digital

Another possibility is a variation of Ludlow-Wartburg-Fraktur (Ludlow, ca. 1920)
http://luc.devroye.org/GerhardHelzel--LudlowWartburgFraktur-after-Ludlow-ca1920.png