Days before his death this summer, 39-year-old Max Spiers texted his mother these words: "If anything happens to me, investigate." The Brit just happened to be a well-known figure in the world of UFO researchers, and now conspiracy theories are running wild.

Authorities in Poland, where Spiers died, say it was natural causes, and the British government has declined to investigate, reports the Independent. His peers in the UFO community, however, are more than a little skeptical.

Kerry Cassidy at Project Camelot says "the entire circumstances are suspicious and I urge everyone to encourage [the release of details] about what really happened and call for an autopsy." Another UFO blogger says, per SFGate: "Healthy people don't just get sick and die, they get poisoned." According to the Telegraph, Spiers had been invited to Poland to speak about his theories at a conference.

Friends say he had been staying with a woman in Warsaw ahead of the conference and was vomiting black liquid and suffering from migraines before being found dead on a couch.

Spiers' mother, Vanessa Bates, describes him as a "very fit man who was in good health," and she fears her son made enemies after "digging into dark places." But UFO expert Nick Pope tweeted Sunday that the idea of Spiers being silenced is a little much.

"Having run the UK government's UFO project I promise we don't go around killing UFO researchers." (Only in Roswell could police investigate a missing flying saucer.)

This article originally appeared on Newser: UFO Researcher's Odd Death Raises Eyebrows

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