You say it charges normally. What charger ? What voltage does it stop at ? It obviously isn't really taking a charge or discharging in 10 seconds would get something VERY VERY hot.

It sounds like either you have a short, in which case I'd expect the charger to refuse to touch it, or all the cells are dead which is pretty unlikely unless whoever made the pack made a real hash of it, perhaps putting one or more cells in reversed.

Steve