Any suggestions as to how to report this?
Leo The Lion explained the methodology.
PM [Personal Message] myself or another Moderator and any issues can be looked into.
It is assumed that any works uploaded belong to the uploader, or, if another's work is used then appropriate consent is sought/received/included, or the image, etc is freely available for public re-use.
See "The Rules" .... #1
Don't confuse 'free for personal use' as 'free to upload/redistribute', as the latter is what artists' copyright is all about....