An arrangement for arresting a seat of a vehicle includes an elongated stationary element which is provided with a row of separate recesses being arranged on the element so as to correspond to a plurality of possible positions of the seat. At least two blocking elements are provided for joint movement to a rest position in which the seat is free to move lengthwise of the row of recesses; each of the blocking elements is movable independently of the other from the rest position to an arresting position in which the blocking elements are inserted in respective recesses independently of one another to thereby prevent further movement of the seat.