Go into the Galley, all photos. Press the menu button and tap "select items." Next, select those images you want to delete, and tap the delete button.
I did as suggested. It did not work. It would ask if I wanted to delete the items, but after deletion, they were still there.
I unmounted my card and remounted it. The thumbnails disappeard and were not counted, BUT a couple of days later after reboot, they were there again.
Should I copy all neede folder to a PC and reformat the card? If so how to do it correctly?