A filter element comprising a pleated metal fiber fleece is pleated according to pleating lines, providing an edge with pleat openings to be closed to make gas flowing through the metal fiber fleece. The filter element comprising at least two flanks, each of these flanks comprises a thermally and electrically insulating fabric and a stiff material layer. The thermally and electrically insulating fabric is present at one side of the stiff material layer, providing a thermally and electrically insulated side to the flank. The metal fiber fleece is mounted between the thermally and electrically insulated sides of both flanks, which exercise a clamping force on the edges of the metal fiber fleece in a direction essentially parallel to the pleating lines, while the flanks closing said pleat openings.