Paranormal Investigator Dan Rivera’s Cause of Death Was Natural After Annabelle Doll Tour

A cause of death has been determined for the paranormal investigator whose body was foundin July after an event in Gettysburg, Pa., showcasing the infamous Annabelle doll. 

Dan Rivera, a senior lead investigator for the Connecticut-based New England Society for Psychic Research, died on July 13, one day after an event featuring the purportedly “haunted” toy that has long been featured in horror tales.

Francis Dutrow, the Adams County coroner, said in a statement on Thursday, Sept. 4, that Rivera’s cause of death was cardiac-related and was ruled as natural.

“Mr. Rivera had a known history of cardiac issues, which were consistent with the findings. It is also confirmed that Annabelle was not present in the room at the time of his passing,” Dutrow said.

A July 13 report from the Pennsylvania State Police detailed the conditions in which Rivera, 54, was found.

“Members from PSP Gettysburg responded to a hotel in Straban Township, Adams County for a report of a deceased [man]. The decedent was discovered in his hotel room by workers,” the report read. “Nothing unusual or suspicious was observed at the scene.”

Rivera had been with colleagues that morning but said he was feeling sick and was going back to his room, Dutrow previously told PEOPLE, although it wasn’t unclear what Rivera may have been ill with.

At the time of his death, Rivera was on tour in Gettysburg to show Annabelle, which the New England Society for Psychic Research has described as “demonically possessed.”

According to the society, Annabelle’s origin dates back to 1968, when she was presented to a student nurse as a gift.

The nurse allegedly took the doll to her home where she lived with her roommate.

“Almost immediately, the roommates noticed strange occurrences with the doll and they were introduced to a medium who told them the doll was inhabited by the spirit of a young girl named Annabelle,” the society has said. “The two roommates tried to accept the doll’s spirit and please it only to have it reciprocate maliciousness and violent intent.”

Husband and wife Ed and Lorraine Warren, who founded the society, removed Annabelle from the home and stored it in a glass box “to contain the evil spirited entity,” where it remains today. 

Annabelle and the Warrens inspired the horror film franchise The Conjuring.

Harrison Jones, a journalist for the Hanover, Pa.-based Evening Sun, attended the tour just one day before Rivera’s death, telling PEOPLE afterward that Rivera “definitely struck me as a kind and very welcoming person, and my heart breaks for his family and colleagues.”

Joining a tour group, Jones started taking photos and video footage as Rivera spoke with the visitors before he took them to see the doll.

“Mr. Rivera, along with another of NESPR’s investigators, Wade Kirby, spoke to the group about Annabelle’s history and their experiences working with the doll,” Jones said. “Among those discussions, Mr. Rivera spoke about how he had built the case that Annabelle was in himself, and that he had designed many aspects from the perspective of his faith.”

Jones said he didn’t speak much directly with Rivera but that the paranormal investigator “did ask me if I got what I needed out of my visit and asked if I had gotten good images during the tour.”

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On July 14, while Jones was working on his story about the event, he heard the news that Rivera had died.

“It was clear from the prior controversy surrounding the tour that his death was going to immediately cause intense controversy and become his own part of paranormal legend no matter what was said,” Jones told PEOPLE. “But in my own reporting I was mainly concerned with trying to focus on the human life lost at the center of this tragic news, Mr. Rivera, who had dedicated so much time and effort in sharing his love for the paranormal.”

In a previous statement shared with PEOPLE, the New England Society for Psychic Research remembered Rivera as not only a “vital part of our team for over a decade, but also a deeply compassionate, loyal, and dedicated friend.”

“Dan’s passion for the paranormal was rooted in a genuine desire to educate, help, and connect with others — whether through social media, conventions, or investigations with local families seeking understanding and peace,” the society said. “We understand that Dan’s work inspired fascination and curiosity for many, but above all, he was a father, devoted husband, and loyal friend, someone who meant the world to those closest to him. Out of respect for his family, we kindly ask for privacy as they mourn this tremendous loss.”