The arson attacks on France’s high-speed rail network hours before the opening of the Olympics may be linked to radical left-wingers and groups critical of the Olympics, the daily Le Parisien reported. A letter claiming responsibility and containing references to ultra-leftist groups was sent to several French and international media outlets, Le Parisien reported Saturday evening. The alleged perpetrators claimed responsibility for the arson attacks on Friday and suggested that their motive was to disrupt the Olympic Games. “You call it a celebration? We see it as a celebration of nationalism,…