A circuit interrupter includes a cylindrical container (5) having an arcuate inner wall of electrically insulating material and containing an arc extinguishing fluid. A rotary shaft (7) is provided along an axis of the container (5), at least one stationary contact (3 or 4) is provided at a predetermined position on the inner wall, and a movable contact (6) is mounted on the rotary shaft (7) in such manner as to be brought into and out of engagement with the or each stationary contact. A closing member (15) is disposed at one end of the opening movement path of the movable contact (6) and substantially closes the clearance between the inner wall and the rotary shaft (7) and, when the interrupter is opened, sweeps along the inner wall of the container (5) towards the closing member (15) to compress the arc extinguishing fluid between the two members (15, 16). The compressing member (16) has a blow outlet (18) which causes the compressed fluid to blow into the space where arcs are generated upon cpening of the interrupter.