Removing duplicates (instead of merging)

I ran a duplicate search and found 21 duplicate entries. I did not find any option to delete the duplicate entries. There is only an option of merging the duplicates. If I merge the duplicates, another pdf file is NOT removed, instead (2) is added on top of the name (so the duplicates still remain in the folder). How I should delete these duplicates through Mendeley itself? Thanks in advance.