A mystery uniform of the Great War

[Shadow of the East Prussia]

I must admit, that I've been trying to "research" it by myself for a long time, but I was never able to find a 100% sure answer. This photo was in my collection for almost five years, and for the first couple of months I was thinking about the Russian unit. Now I'm not entirely sure. This photo was found in Czech Republic, and certain parts of uniform doesn't match, so I'm not sure if they could be Bulgarians, or maybe Russian Civil War soldiers?

If anyone could identify these guys, I would be very grateful! It's not the only mystery I've got in my collection, but probably the second most disturbing

[PF]

Placed query at http://1914-1918.invisionzone.com/forum ... pic=226734

Hope this helps!

[Shadow of the East Prussia]

Someone has identified this photo for my via the PM Indeed, they're Bulgarians, 9-ти пехотен Пловдивски полк. http://www.forum.bg-nacionalisti.org/in ... ic=1121.45 So the Balkan Front...