Looks like a press control bar -- it's ouside the bleed areas and won't be in the finished work. It must be either part of another linked graphic, or placed there by itself. Check the Master page.
Thanks Peter for getting back. It is very strange. It is not on the master page and is not part of a linked graphic, Each colored square is a separate frame. It defies all my efforts to delete it.
Stop Press: I finally managed to group it and delete.
Ps I don't know why every post is marked Correct Anser
Glad you got it sorted.
What seems to you to be the "Correct Answer" is actually a button so the poster can MARK the correct answer. I agree it's confusing.
Thanks Steve. I understand the 'correct answer' now. However, as you say it is very confusing. It would be better marked 'click here if you consider this to be the correct answer'.