Barrier elements provide security from terrorist threats by ability to withstand both vehicle collisions and explosive blasts. Each barrier element is prefabricated to include a massive block of durable material, preferably of high strength concrete, with at least one tunnel extending at least partially between respective cavities in two opposite sides of the block. Each barrier element also includes at least one beam that is preferably made of steel and extends through one such tunnel. Multiple blocks are positionable slidably on top of the ground side-against-side with their beams coupled longitudinally to one another at least approximately end-to-end. Retainer means can be used to block coupling means from entry into the tunnels. Forces from a vehicle collision or an explosive blast can cause barrier elements to rotate relative to one-another when the couplings between beams hinge or bend as the durable material that interferes with the rotation breaks away.