“it is believed”???
No it’s BS. Phosgene kills.
B-2 bombers on the way to Paris?
No actual person believes this report. It would be stupid of the face of things, if for no other reason than there are vastly more effective gas agents to control crowds than phosgene.
Phosgene does not kill immediately, it causes the protein in the alveoli to congeal, making it impossible for these parts of the lung to absorb oxygen. The victim actually dies of asphyxiation. perhaps a day later.