Perhaps the strangest tale of the original 1947 rash of flying saucer sightings was told by two Tacoma timber salvagers. As later published by Kenneth Arnold and Ray Palmer (The Coming of the Saucers, 1952), Harold Dahl reported observing six large “doughnut-shaped” vehicles while boating near Maury Island on June 21, 1947. One appeared distressed and spewed chunks of debris that rained on Dahl's boat, killing his dog and injuring his son. After taking shelter on the island, Dahl returned to Tacoma and showed the evidence to his employer, Fred Crissman.
Shortly after Kenneth Arnold's June 24, 1947, encounter with “flying saucers” over the Cascades made national headlines (on June 26), Crissman offered two fragments of the alleged UFO to pulp science fiction magazine publisher Ray Palmer. Dahl also said that a mysterious “man dressed in a black suit” had menaced him and fogged his photographs of the incident.
Palmer retained Kenneth Arnold to investigate, and he in turn called in two U.S. Army specialists who had followed up on his own UFO report. They took a box of “evidence” for examination but died when their B-25 airplane crashed on August 1, 1947, en route from Tacoma to San Francisco. The Tacoma Times reported that the plane might have been “sabotaged or shot down” to prevent inspection of its cargo.
The FBI immediately began an investigation, and Dahl and Crissman confessed that they had fabricated the flying saucer story. The “debris” consisted of bits of scrap and pumice from a Maury Island beach. The U.S. Army and survivors confirmed that the plane crash was caused by an engine fire. Despite this, the dramatic 1952 account of the “Maury Island Mystery” spawned persistent rumors that “men in black” and a government conspiracy are suppressing the truth about flying saucers.
Update: In April 2007, the Seattle Museum of Mysteries arranged for an analysis of debris recovered from the B-25 crash scene. Preliminary findings indicated that mineral remains were ordinary igneous rocks or, possibly, fragments of a meteor.