Security window or door

A security structure for protecting an opening in a building, comprising at least a first plate-like panel on an attack susceptible or outer side of said window, and a second plate-like panel arranged parallel to and a distance away from said first panel on an inner side of said window away from said attack susceptible side to enclose a space between said first panel and second panel, a first frame comprising separate first frame sections for enclosing said first panel, a second frame comprising second frame sections for enclosing said second panel, whereby said first panel and said second panel are mounted with their respective frames within a soffit surrounding said opening, and at least one of said first frame sections is held a distance away from said soffit to form a gap which provides a venting flow connection between said space between said first panel and said second panel with the outside of said window, said structure further comprising a first security member of a bullet-proof material, and a similar second security member also of a bulletproof material, whereby said first security member is attached to said first frame on a side facing said second frame, and said second security member is attached to said second frame on a side facing said first frame, whereby at least one of said security members overlaps edge areas of one of said panels, and at least one other of said security members overlaps the area of said gap, and wherein said first and second security members partially overlap each other in the vertical direction.