I've read What to do when plagiarism is discovered, which says this about a pattern of plagiarism:
If it looks like there is an egregious pattern of plagiarism, and deletions seem necessary, flag for moderator attention. Explain that you believe the answer has been plagiarized, and paste the source URL into a comment underneath, say
Plagiarism: copied without attribution from ....
If I've found (say) six examples from a user, should I flag them individually, or raise a single flag on one of them and list all six occurrences?
I don't want to create extra work for mods with multiple flags, but I could easily run out of space in the flag box...