In the early hours of 1977-04-25, a Chilean Army detail was stationed at Pampa Lluscuma, near the Andean town of Putre in northern Chile. Contemporary press commonly described the group as a patrol, but later reconstruction indicates that the eight soldiers, Armando Valdés Garrido and seven conscripts, were guarding Army horses in the area rather than conducting a conventional patrol exercise. The isolated high-altitude location lay in a strategically sensitive part of northern Chile during a period of regional military tension.

According to accounts of the event, one of the soldiers first observed a bright object descending behind nearby terrain. A second luminous object then appeared and remained much closer to the group. Descriptions generally characterize this second phenomenon as an intense violet or purple light with reddish features at either end, positioned roughly 500 meters away. Witnesses reported that the object or light produced no readily identifiable sound. The soldiers also described unusual behavior among the horses, and Valdés ordered the campfire concealed while the group watched the phenomenon.

Valdés eventually moved away from the other soldiers and toward the direction of the light, reportedly demanding that whatever produced it identify itself. The remaining soldiers then lost sight of him. Approximately fifteen minutes later, Valdés returned to the group under circumstances subsequently described in dramatically different ways. Early retellings portrayed his return almost as an instantaneous or unexplained reappearance, while later testimony from Valdés described him as having remained close to the camp but outside the other soldiers' field of view.

The fifteen-minute interval became the central mystery of the case. The soldiers reportedly described Valdés as confused or physically affected upon returning. Accounts attributed to witnesses also claimed that he spoke words resembling: "You do not know who we are, nor where we come from, but we will return." Valdés then reportedly lost consciousness or slept for a period before recovering.

Two additional details transformed the incident from an unusual light sighting into a famous alleged missing-time or abduction case. Retellings claimed that Valdés, who had recently been clean-shaven apart from a moustache, suddenly displayed several days of beard growth. His calendar wristwatch was also reportedly found stopped while displaying 1977-04-30, five days later than the actual date. These details were repeatedly cited as apparent physical evidence that Valdés had somehow experienced five days during the roughly fifteen minutes in which the other soldiers could not see him. However, the evidentiary foundation for both claims is considerably weaker than their prominence in later retellings suggests.

The incident rapidly attracted press attention in Chile and abroad. An Associated Press story published in May 1977 presented the event internationally as a strange encounter in which a Chilean soldier had apparently "lost" five days. The Chilean Army did not officially endorse an extraterrestrial interpretation. Later reconstruction of the case indicates that the Army acknowledged that press versions broadly corresponded with information obtained from members of the unit while avoiding an official judgment concerning the nature of the reported phenomenon.

Over subsequent decades, the event became one of the most famous UFO cases in Chile and was commonly presented as an alien-abduction incident. Researcher and journalist Patricio Abusleme Hoffman later revisited the episode, located participants, and examined the evolution of the story for the book La noche de los centinelas. That later investigation is particularly important because it documents how the interpretation of the fifteen-minute disappearance changed as Valdés himself began publicly rejecting the abduction narrative.

From at least the early 2000s onward, Valdés repeatedly stated that he had not been abducted. During a public appearance in 2013, he explicitly declared that there had been no abduction or close-contact experience. His later account maintained that he had moved behind a wall or otherwise beyond the other soldiers' view while attempting to observe the strange light and remained close enough to hear the group. When he returned suddenly, the already frightened soldiers interpreted his reappearance as considerably more mysterious than Valdés believed it had actually been.

That later account substantially weakens the classic abduction interpretation, particularly because the individual supposedly abducted denied that the abduction happened. It also requires the famous beard-growth and altered-watch claims to be treated cautiously rather than as established physical evidence of a time anomaly. Later investigators have identified substantial uncertainty concerning those details and their evidentiary documentation.

However, rejecting the abduction interpretation does not automatically explain the entire incident. Valdés continued to acknowledge that the group encountered an unusual luminous phenomenon. Multiple soldiers were reportedly present when the lights were seen, and the original sighting of the luminous objects is logically separate from what happened during the approximately fifteen minutes in which Valdés was outside the group's view. The evidence therefore supports distinguishing between a multiple-witness anomalous-light report and the much less securely supported claim that Valdés was physically abducted or experienced five days of missing time.

The Cabo Valdés Incident is particularly valuable as an example of how a real reported anomaly can acquire more extraordinary characteristics through press coverage, witness interpretation, ufological investigation, and repeated retelling. The later rejection of the abduction narrative by Valdés should be included prominently rather than treated as an inconvenient footnote, but it likewise does not justify pretending that the original soldiers reported nothing unusual. The strongest unresolved question is therefore no longer whether Valdés spent five days aboard an extraterrestrial craft, but what produced the unusual luminous phenomena reported by the military group at Pampa Lluscuma.