Default Nexus 7 stuck on formatting

Hi, yesterday I tried format my Nexus 7 in Settings menu. After 10 hours it is stuck in this screen.

English meaning is "Deleting..."
I was using stock 4.4.2 rom with stock recovery. I tried start bootloader mode but it was started same screen. Can you help me, thanks.
NeXus One
NeXus 7