Abstract: A corrosion resistant intruder screen has a frame including elongate frame members (3) with a mesh (4) clamped to frame members (3). The frame members (3) each have a first holding channel (50) formed therein and a clamping portion (6) spaced from the first holding channel (50). Clamping members (7) co-act with fastening means (8) to clamp the mesh (4) between the clamping members (7) and the clamping portions (6) with leveraged clamping action. The screen includes covers (54) which are configured to be clipped to the frame members (3) and which each have a second holding channel (60) formed therein. The screen further includes a sealing assembly comprising first sealing members (51) and second sealing members (61).