Abstract: The present invention relates to a security panel (1), for example for use in a security barrier, and to a method of forming the security panel. The security panel (1), comprises an expanded metal mesh (2), the mesh hating apertures (9) therethrough bounded by a plurality of sides (11), at least one of said apertures (9) having at least one side (11) to which is affixed a separate barbed structure (4), the barbed structure having at least one barb (14) extending in a plane of the panel (1) in towards another side (11) of said aperture (9).