Dan Rivera collaborated with the New England Society for Psychic Research (NESPR), which is presently conducting a national tour across the US, showcasing the notorious Annabelle doll.

Rivera died suddenly on Sunday, while the company was in Gettysburg, Pennsylvania, the NESPR said in a post to Facebook.

“With heavy hearts we share the sudden and heartbreaking loss of our dear friend and colleague Dan Rivera,” the statement reads.

“MESPR is devastated by his passing and is still coming to terms with this profound loss.”

Rivera, a lead paranormal investigator and US Army Veteran, frequently participated in events like the “An Evening with Annabelle” experience.

The Annabelle doll gained fame through the horror film The Conjuring, which was based on a real rag doll bought from a 1970s hobby store by a mother for her daughter, a nurse.

Annabelle was reported to move on its own and leave notes and “psychic slashes” on her victims.

She was handed over to the late paranormal investigators Ed and Lorraine Warren, who kept the doll in their occult museum in Connecticut.

The doll was said to cause disasters whenever she was moved to another city for touring.

It is the most infamous allegedly haunted/cursed doll among paranormal believers.

NESPR said while Rivera’s work “inspired fascination and curiosity,” above all, he was a “father, devoted husband and loyal friend”.

His cause of death has not yet been determined. 

The company said it is trying to figure out a path forward to continue Annabelle’s tour of the US without Rivera.