OUT THAT THE UFOS ENCOUNTERED THUS FAR BY HIS PILOTS HAVE APPEARED TO POSE NO EXTRATERRESTRIAL THREAT ... AND THAT THERE IS STILb.NO PROOF THE UPOS ARE OF EXTRATERRESTRIAL ORIGIN OR FLOWN BY INTELLIGENT BEINGS. MOREOVER, HE WARNED, ... ARE FLOWN BY INTELLIGENT BEINGS OF EXTRATERRESTRIAL ORIGIN. TRETYAK SAID HE WOULD NOT, AT THIS TIME, TAKE ...