A controlled explosion is a method for detonating or disabling a suspected explosive device.
Methods which are used to set off a controlled explosion include clearing the area and using a bomb disposal robot to attach a shaped charge to the suspected bomb to sever the explosive from its detonator.
Another classic method of controlled explosion is to place the suspected bomb in a skip and fill it with sand before detonating it with a self-incendiary device or a fuse.
References
Controlled explosion Wikipedia(Text) CC BY-SA