There have been several untimely death reports in the US that have been associated with UFOs, sparking questions regarding how people could have been killed by an alien species.

These cases include the death of a US Air Force pilot who passed away shortly after claiming to see a UFO and a Brazilian man who ended up "zapped" by an extraterrestrial species.

Murdered by UFOs

UFO researcher Nigel Watson has explained such bizarre cases in some of his write-ups, shedding light on their odd nature. He has spent several years examining global UFO reports and has published various reports and books about his findings.

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Thomas Mantell UFO Incident

One of these bizarre cases was the death of Thomas Mantell, a captain of the US Air Force. He was asked to look into a conical and silvery flying object back in 1948.

Based on reports, Mantell, who was also a 25-year-old hero from World War II, and three more pilots were having training exercises when they received the request to look into the odd object.

Mantell shared that it was apparently a metal object or a reflection of the Sun from a metal object. It also appeared to be massive.

In order to intercept the bizarre object, three planes breezed 22,000 feet through the air. Mandell reported the status of the object as they did so.

However, shortly after, two planes had to back out due to insufficient oxygen supply. This, however, was not the case for Mandell, who kept going higher and eventually reached 25,000 feet into the sky.

Later on, debris from Mandell's plane was found in Shelby County.

Initially, the US Air Force claimed that Mandell was chasing Venus. However, they later said that the object was actually a CIA-sponsored Skyhook balloon that was released in Southern Ohio.

Watson explained that UFO believers still think that Mantell died at a murderous UFO's hands, as the explanation of the Skyhood case was not revealed until the 1960s.

Green Death Ray

In August 1967, Inacio de Souza, a Brazilian man, and his wife were returning home when they witnessed an object with the shape of an inverted wash basin. They also witnessed three men wearing clothes that were extremely tight.

Out of reflex, Souza used his rifle to shoot one of the men, seemingly leading to no effects. However, a green ray light apparently shot to Souza's head.

Souza ended up falling unconscious and experiencing tremors and numbness in his hands and head.

Doctors claimed that Souza experienced hallucinations. The man was also diagnosed with leukemia after a few days. His condition quickly progressed, leading to his ultimate demise in October 1967.

Watson explains in a book that while there are ufologists who believe that the illness and encounter were just a coincidence, others think that the UFO's green ray was a strong and deadly radiation beam,

Maury Island Incident

Back in 1947, Harold Dahl, with his son and a duo of crewmen, were aboard a tugboat off Maury Island. This was in Puget sound, in between Tacoma and Seattle.

The men reportedly witnessed six silver and golden donut-shaped objects over them. One of these objects appeared to wobble before expelling a rain of black lumps and thick metallic strips.

One of the showered objects struck the boy's arm, resulting in burning. The dog that was with them also ended up dying.

Fred Lee Crisman, Dahl's boss, went to the site and gathered some debris.

Dahl was reportedly confronted by a man in a dark suit who drove a black sedan. This man brought Dahl to a Tacoma diner and warned him to keep his mouth shut.

Kenneth Arnold, who witnessed the odd objects just a few days before, reached out to the Air Force Intelligence for assistance. In July 1947, Lieutenant Frank Brown and Captain William Davidson were sent to Tacoma. However, they did not find any molten lead rain fragments and believed that the fragments appeared to be smelting paint slag.

Both Brown and Davidson passed away when the B-25 they rode crashed as they were on their way to the base. With this, several photographs and samples linked to the case ended up vanishing.

Watson explained that several think that this was a cover-up of military intelligence.

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