In this post a Russian tank drives over a mine. Are the Ukrainians using mines in the war? I doubt that they would mine their own country, and even more so if they still need to advance over the area that they have previously mined.

Or is this a Russian mine? Seems unlikely that they would mine their own path.

3rd theory: this was not just a random mine, but specifically placed there by a special UA recon team or something? But if the Russians stop using this path, then it still leaves the same problem of Ukrainians mining their own country, and territory that they have to advance over at a later stage.

I don't know much about military tactics etc. I'm just curious.