A wide range of voltages can be dangerous for different reasons. A very low voltage (such as that produced by a single torch battery) can produce a spark powerful enough to ignite an explosive atmosphere. Batteries (such as those in motor vehicles) can also overheat or explode if they are shorted.
If a person comes into contact with a voltage above about 50 volts, they can receive a range of injuries including those directly resulting from the electrical shock (stopped breathing, heart, etc), and indirect effects resulting from loss of control (such as falling from a height or coming into contact with moving machinery). The chance of being injured by an electric shock increases where it is damp or where there is a lot of metalwork.