Project Blue Book Case #8766. On the afternoon of April 24, 1964, Socorro police officer Lonnie Zamora was pursuing a speeding car south of town when he heard a loud roar and saw a flame in the sky. Abandoning the chase, he drove toward the disturbance and discovered an egg-shaped, white metallic craft sitting on legs in an arroyo, with two small figures in white coveralls standing beside it.
As Zamora approached on foot, the figures noticed him and moved quickly to the craft. The object emitted a loud roar, produced a blue-orange flame from its underside, and rose vertically before departing at high speed to the southwest. Zamora, shaken, radioed for backup. Sergeant Sam Chavez arrived within minutes and found burning brush and four angular impressions in the ground where the craft's legs had rested.
The Socorro case became Blue Book's most thoroughly investigated encounter. J. Allen Hynek personally investigated, as did FBI Agent Arthur Byrnes. The physical evidence — the landing-gear impressions, the burned vegetation, and Zamora's detailed testimony — made this one of the few Blue Book cases with tangible trace evidence. Zamora was a respected officer with no history of sensationalism, and his emotional distress was evident to all who spoke with him.
The Air Force investigated for months, considering and rejecting explanations including experimental aircraft from White Sands (which denied any test flights in the area), student hoaxes, and natural phenomena. No satisfactory conventional explanation was found.
The case was classified "Unknown" — and is widely considered the single most important and credible close encounter in Project Blue Book's 22-year history.