I found a few topics on this, but I still don't understand what pictures in this folder are used for. My problem is that it is getting quite huge, and I think the only actually used pictures are the ones in media/k2/items/cache (the resized versions of what I can find in src if I got it right). All other pictures used in articles are in authors' folders, so I don't understand if it is safe to purge everything in media/k2/items/src.
Any idea?

Hello,
You can safely remove the items of the media/k2/items/src folder.

Thanks!

You are welcome.