French astronomer and computer scientist Dr Jacques Vallée went to South America to investigate and document reports of UFO close encounters that have resulted in the death or injury of witnesses and published the results in his book "Confrontations."
Among the numerous cases he studied in South America, he dealt with the 1977 events in Colares:
It is in the islands around Belém, where the waters of the Tarantins and the Amazon majestically come to meet the ocean one degree south of the equator, that the 1977 Brazilian wave culminated; and it is there that for the first time the proof of the reality of the phenomenon was obtained. More specifically, as Daniel Rebisso has revealed, the culmination took place over a three-month period from July to September 1977 on the island of Colares and on the beach of Baia do Sol, on the island of Mosqueiro. (Ref. Rebisso Giese, OVNI no Para)
We found fishermen there who had witnessed the objects, and a doctor who had ministered to the medical needs of dozens of people hit by the light from the chupa. She confirmed that one of her patients died after the experience. Several of these witnesses also told us that they had observed two teams of Brazilian military filming the objects, attempting contact.
Ground truth: there was no denying the wave of 1977. It started in June near Cape Gurupi, north of the town of Vizeu, and it moved in both directions along the coast: toward São Luís to the east and toward Belém to the west during June and July; it reached a peak in September and October.
The reason the phenomenon could not be denied was very simple: every evening the UFOs appeared, coming from the north. In some cases, they flew down from the sky, in others, they emerged out of the ocean. I saw a photograph of an object with a luminous white ring flying right out of the brackish water at dusk.
They came over the islands at low altitude and circled; they descended as if to land; they made loops and accelerated suddenly; they hovered over houses and probed the inside with beams. They even emerged out of larger objects and reentered them. And this happened on schedule, every evening for three months.
Vallée discussed with Dr. Carvalho and wrote this list of symptoms from the Doctor's patients medical records:
A feeling of weakness; some could hardly walk.
Dizziness and headaches.
Local losses of sensitivity. Numbness and trembling.
Pallid complexion.
Low arterial pressure.
Anaemia, with low hemoglobin levels.
Blackened skin where the light had hit, with several red-purple circles, hot and painful, two to three centimetres in diameter.
Two puncture marks inside the red circles resembling mosquito bites, hard to the touch.
Hair in the blackened area fell out and did not rejuvenate, as if follicles had been destroyed.
No nausea or diarrhea.
After asking various forensic pathologists to peer-review his findings, Vallée claimed that "what UFO witnesses describe as light may, in fact, be a complex combination of ionising and non-ionising radiation. Many of the injuries described in Brazil, however, are consistent with the effects of high-power pulsed microwaves." He later pointed out that pulsed microwaves may "interfere with the central nervous system. Such a beam could cause the dizziness, headaches, paralysis, pricklings, and numbness reported to us by so many witnesses."
In the conclusion to "Confrontations" Vallée discusses whether the Brazilian UFOs such as those seen at Colares are deliberately trying to kill people. If they are, he considers that they are fairly inefficient at doing it. After all, someone in a helicopter with a high powered rifle and night scope, could probably do a better job. He does however point out that a radiation beam that was designed merely to stun people at one range might be lethal at another range.
Given that there is evidence that research has been done into High Powered Microwave (HPM) weapons, Jacques Vallée ponders the relationship between human and alien technology. "Here again, the UFOs seem to represent an alien force that anticipates our own scientific developments by decades, mocking our own efforts to identify its nature and its long term intentions." (Vallée, 1990, p.206)
A general conclusion offered by Vallée at the end of "Confrontations" is:
"The material gathered in this book represents only a portion of the cases I have personally investigated and a very small percentage of the data compiled by other researchers and by official agencies. The realization that none of this material has ever been seriously examined by professional scientists is staggering. Strictly in terms of the sociology of science, the refusal to consider the facts of the phenomenon is a remarkable statement about the narrow limits within which our society authorizes the serious pursuit of knowledge."
Actually the example of Colares indicates that in this case the UFOs light beams served some other purpose than just to hurt people. What exactly the purpose of this targeting was remains a puzzle.