Dangerous Death of a Hot-glue Gun

I was just going to plug in my hot-glue gun, as always. But something strange happened this time when I plugged it in. It made a pop and made a small fireball on my desk. Although it didn't light anything on fire it would have been dangerous if I had that bottle of methalated spirits on my desk, Which was stationed about 1 meter away from the hot glue gun.

I dismantled it just to show the burnt innards of it...

Enjoy the pictures!