I have a galaxy 7s thru Verizon. How do I delete pictures in the sent/received folder?

[AC Question]

The pictures in that folder only appear when I am attaching a picture to an email..I have gone to my gallery, but this folder does not appear in my gallery.

 

[Rukbat]

They're hidden, so they won't show in Gallery. (Gallery doesn't have its own folder - it shows all non-hidden pictures in the phone.)

Use My Files, find the folder the pictures are in and delete them.