I'm looking for a French film. The film is set in late 70s or 80s. The film starts with a traffic accident involving a military vehicle transporting chemical weapons, toxins.
The plot involved accidental military chemicals, poison spillage (almost certainly agent orange). Military was forced to cover up the accident via burning down small town. There are quite memorable shots of military in protective suits systematically burning down small town. The plot obviously involved investigation by skeptical journalists and uncovering military's involvement and cover up.
Uncovering the military's involvement includes tense conversations between investigative journalists and military/scientific informer, with the latter revealing classified military programmes involving almost certainly Agent Orange. I am sure of the fact that the Vietnam War and Agent Orange were mentioned. This scene reminds me of Jacob's ladder (1990) that involved similar revelatory scene also using ex military informant.