Thanks.
Its not the use of the images so much, it is linking directly to them.
Google analytics sees this as, for example, 30 images x 300 view each = 9,000 page impressions in a very short space of time and could think I am 'spamming' to increase my search ratings.

If I use multiple images like that myself, I either combine them into a single image first, or upload each of them to the bb separately rather than linking.