BRISTOL, R.I. (WPRI) — It’s been nearly 24 years since the partial remains of a Roger Williams University student washed ashore on Hog Island.

But to this day, the mystery surrounding Bryan Nisenfeld’s death has haunted investigators.

“We don’t have the evidence to say ‘yes, it was a homicide’ or ‘no, it wasn’t a homicide,'” Bristol Police Detective Julie Veader said. “That’s why the case is open.”

Bryan’s mother Marianne Brown remembers the day she learned her son had vanished without a trace.

“My husband called me and said, ‘do you know where Bryan is? and I said, “what do you mean?'” she recalled. “The university called and said he’s missing … I was like, ‘oh my God how? I don’t understand.'”

The 18-year-old freshman was a true intellect, according to Marianne, but had made it clear he was struggling at school. Over Christmas break, he told his parents he wanted a change.

“His father and I said, ‘just stick it out until the end of May and you can transfer,'” she recalled.

Feb. 6, 1997, was the last day anyone saw Bryan.

His disappearance sparked a six-month manhunt, but that all came to a tragic end when a beachgoer found a boot containing a human foot on nearby Hog Island. DNA testing would later reveal it belonged to Bryan.

What led to Bryan’s demise remains a mystery, but Marianne has her own theories.

“I truly believe he was murdered,” she said, adding that he’d received a threatening phone call shortly before he went missing.

But Veader and her colleague, Bristol Police Major Scott McNally, said there’s no proof of foul play.

“Ultimately, it’s putting a puzzle together,” McNally said. “We’re looking for a missing piece to that puzzle and if we can find that missing piece, it takes us and puts us in a better position to solve the case.”

More than two decades later, a spokesperson for Roger Williams University tells 12 News the institution has remained cooperative throughout the investigation and will continue to be as the search for answers begins anew.

“We were and continue to be deeply saddened by the loss of Bryan,” the spokesperson said. “Roger Williams University takes any student loss or missing student case very seriously and we worked with the local and state authorities on a thorough investigation at the time and continue to remain cooperative.”

With only partial remains, the cause of Bryan’s death is still undetermined. But detectives aren’t giving up hope that one day, they’ll uncover the truth.

“No stone is left unturned,” Veader said. “What will solve this case is some good old-fashioned police work. We get a lead and then we’re digging. We’re on our way.”

That quest for closure is just as strong for Marianne.

“I miss him,” she said. “He was my everything.”

Anyone who believes they may know what happened to Bryan is urged to contact the Bristol Police Department at (401) 253-6900.

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