The photos seem to originate from a Russian Livejournal-account with at least one post in English explaining what appears to be quite serious, non-facepalm inducing cosplaying/Live action roleplaying.
EDIT: Apparently these people play S.T.A.L.K.E.R. (great pics!) around the Chernobyl site as well (thx, Jonatan).
[via:Zele]