The following was released at 6 a.m. Tuesday, June 18:

"An experimental device designed by Livermore Laboratory was fired at 4:45 a.m. today. The device was suspended under a balloon at about 500 feet above a Yucca Flat firing area."

"The Wilson shot had been scheduled to be ready June 8, but was postponed 6 days because it was not ready technically, and four days because of forecast of unacceptable fallout or because of surface winds which would have interfered with balloon handling procedures."

"There were some 58 diagnostic and effects experiments on the sequence timer. The programs of military and civil effects, of Desert Rock troop observation, of military training, and of air participation were approximately as announced on June 13."

"The mushroom cloud rose to above 30,000 feet with the top separating cleanly from the stem and being blown north of due east at about 12 knots. The cloud stem dragged at low altitude, moved more rapidly in the middle, and more slowly near the top, making it spread out in a long V. This section, below 20,000 feet, was being blown very slowly to slightly north of due west. Partially because of this 180 degrees of shear and partially because of the balloon placement, with the fireball not approaching the ground, only traces of fallout may be expected outside of the bombing range."

"Because surface winds were light and varible in wind runs prior to the shot with some possibility of light winds out of the north, persons who observed the shot from the Official observer areas and from the control point area were evacuated as a precautionary measure. They began departure at 5 minutes after the shot and the areas were cleared within 30 minutes. By 6 a.m. only very light fallout had been recorded in the Control Point area."

"The Civil Aeronautics Authority advised pilots planning flights within 150 nautical miles of Las Vegas to contact the nearest CAA facilityy for safe routing instructions. Between 6:45 and 8:45 a.m. the CAA closed an area extending from Nevada Test Site to a point 20 miles west and slightly south of St. George, from there to Clark Mountain south of the Nevada State Line in California and back to Nevada Test Site."