If it was Belgian it would have the Belgian proof marks.
In the book I looked in everything matches....grips pattern, grip shape, the safety hole where the missing safety switch is, the English bulldog pattern extractor rod, the hump for the rear sight and most distinctive is the two screws are in the proper position and size (the missing screw is obviously of smaller diameter). I am positive it is a Brong-Petit because even almost identical copies in Spain or Belgium did not exactly copy the grip panel patterns so closely and this gun has an identical grip panel pattern as the Brong-Petit as appears in my book.