Dan Kaszeta, an associate fellow at the Royal United Services Institute, tweeted that “it is legitimately difficult to assess these situations remotely, particularly when we largely have second-hand or third-hand reports rather than actual evidence from the scene”. “We have a handful of sick, but not dead, Ukrainian soldiers,” he added. “They’ve had difficulty breathing and ataxis. This does not tell us much. People leaping onto nerve agent diagnosis from this presentation of signs and symptoms are way off.” He also cautioned that in the area under attack there is “lots of scope” for “conventional or incendiary weapons to cause chemical problems because of fires and explosions”.