This was followed by an admission in May 1992 by President Boris Yeltsin, who had been Sverdlovsk's Communist Party chief at the time of the accident, that the KGB had revealed to him that "our military development was the cause". Based on these reports a team of Western scientists led by Meselson gained access to the region in June 1992. Before they arrived they had been provided by the authorities with a list of 68 known incident victims in Sverdlovsk. By visiting and questioning in their homes surviving relatives of those who had died, the investigating researchers ascertained both where the victims had been living and where they had been during daylight hours at the time during which hospital admission records indicated a possible release into the atmosphere of anthrax dust. When the locations were plotted on maps, the places where the victims lived did not form a clear geographical pattern. However, there was a very precise indication from their reported locations during working hours, that all of the victims had been directly downwind at the time of the release of the spores via aerosol.
