deleting a number of photos from group wall album

I am administrator of 3 groups on Facebook where the wall album has gotten over 6000 photos in with many repeats. I would like to be able to delete a lot of them at once, but not all of them. Any help available about how to do that.

If you wish to delete complete Albums just click the album you want to delete and you will see Edit Photos · Delete Album.
But if there are some you want to keep maybe start new albums for those ones and then delete that album.

Thanks for that answer... I am not sure that I can do this, as it is a group.
I will give it a try and get back to you.
Meanwhile... if there are any other ways to do this please reply.
Thanks again. A Batman smiley... cool.