Samsung Galaxy S2 All Photos disappeared from the Gallary

Hello friends,
I am using Samsung Galaxy S2 from last few months. But the problem came and it was a desaster for me. I was watching pictures in gallery and all of a sudden all photos certainly disappeared and now the same Gallery shows "No items". Is there any way to fix this issue?
Thanks in advance.

there is no way by which pictures from the gallery deleted until and unless you delete it manually. Also check it out that whether the location of images to be saved was phone or sim. And if it is sim then check in to your sim if you have replaced it with some other sim.