On Friday, July 18, 1924, Robert W. Imbrie, United States Consul in Tehran— and personal friend and special agent of Allen W. Dulles, Chief of the State Department's Near Eastern Affairs Division—was brutally killed. Imbrie was beaten to death by a mob led by members of the Muslim clergy and including many members of the Iranian Army. In the weeks preceding July 18, there had been several outbreaks of anti-Bahai violence. Imbrie and Melvin Seymour had gone that morning to investigate a miraculous watering place in central Tehran that figured in the anti-Bahai excitement. According to contemporary accounts, a Bahai had been struck blind after drinking from the source when he refused to make an offering in the name of the Shi'i saints; his sight miraculously had been restored after he had repented and made the donation.
Zirinsky, Michael. (1986). "Blood, Power, and Hypocrisy: The Murder of Robert Imbrie and American Relations with Pahlavi Iran, 1924". International Journal of Middle East Studies, 18(3), 275-292.