A hybrid explosive unit which is intended for artillery shells or anti-tank mines has a casing, an explosive charge in the casing defining an upwardly-facing hollow, a dished element lining the hollow, a metal cylinder embedded in the charge and extending through a center of the dished element, a sheath of inert material surrounding the cylinder, the cylinder and sheath together forming a first projectile of high penetrating power, and, a plate of inert material embedded in the charge across the lower ends of the cylinder and of the sheath, the plate being adapted, upon firing of the unit, to act as an attenuator and diffractor of the detonation wave, and the plate and dished element together forming a second projectile of high penetrating power which travels behind the first projectile when the unit is fired.