Shortly after midnight on September 19, 1976, the Imperial Iranian Air Force command and control center at Mehrabad International Airport in Tehran began receiving calls from citizens reporting an unusual bright object in the sky over the Shemiran district of the capital. An initial check with the control tower confirmed that something brighter than a star was moving unpredictably at high altitude. Brigadier General Yousefi authorized the scramble of an F-4 Phantom II interceptor from Shahrokhi Air Force Base in Hamadan, 175 miles west of Tehran.
As the first F-4 approached the object at about 70 miles out, its instruments and radios suffered a total electronics failure and the pilot aborted the interception. A second F-4, flown by Lieutenant Jafari, launched forty minutes later and began acquiring the object on radar, which appeared to be the size of a Boeing 707. When Jafari closed within twenty-five nautical miles, a small, bright second object separated from the primary and moved at high speed toward the aircraft. Jafari attempted to fire an AIM-9 Sidewinder missile, but his weapons-control panel and radio communications went dead. The smaller object then returned to the primary.
A third object separated from the primary and descended toward the ground. Jafari watched it land softly in a dry lake-bed south of Tehran, illuminating the area for a radius of one and a half miles. A commercial airliner flying in the same sector also reported communication failures when near the object. On landing at Mehrabad, the crew and another F-4 pilot reported that their UHF receiver would not transmit when near the object.
The incident was written up by U.S. Air Force Lieutenant Colonel Olin Mooy and transmitted in a four-page report by the Defense Intelligence Agency. The report, declassified in 1977, listed the case as having exceptional significance because it involved continuous visual, radar, and electromagnetic effects on multiple aircraft. It remains the most thoroughly documented military UFO engagement ever released by a foreign government.