This is going to be a guess. Since you have an android you may have Google doing an auto backup in which under settings sync you may want to turn off the sync for the photos.
Once turned off google will not place them back on your phone.
This can also be done via googles site on the web.
You can also get better directions via google help on the web or this may be covered in your owners manual.
Once disabled you select the photos to delete and they will or should not reappear.