We’ve all seen the shows on Investigation Discovery, 60 Minutes, or 20/20 about murders that go unsolved for years, sometimes even decades. And while DNA and technological advances have led to clues and arrests over the years, many cases have left communities, authorities, and families without closure. One case, in particular, from East Brunswick, New Jersey remains open.

Who killed Betty Jean Belt? On July 1, 1975, the 16-year-old teenager went for a bike ride on Cranbury Road, a rural street she lived on. She never returned home. On July 21, nearly three weeks later, her decomposed body was discovered in the woods by a stream. She was identified through her dental records.

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Her father said she was last seen wearing a pullover blue shirt and blue jeans, and even passed by her on her bicycle while driving home for lunch. According to a Home News report that was released shortly after her body was discovered, “A pair of blue jeans were around the girl’s ankles when the body was retrieved from the ditch and a similar blue shirt was found nearby. The body was clothed in panties and a bra when found.”

Her shoes, wallet, and bicycle were found the afternoon she disappeared. Authorities believe Belt died from injuries sustained during an assault, including jaw and skull fractures.

But what happened to Belt? Who could have killed this innocent teenager? Many have suggested that she ran away or was involved in a cult. Her friends say she was “straight and narrow,” and wouldn’t have gone anywhere with a stranger willingly.

Said friend Diana Lenz, “There is no way Betty would have gotten in a car with a stranger. She wasn’t the kind of girl that would hitchhike. She wouldn’t do that. She was not the kind of kid that would run away. Someone would have had to forcibly take her. There is no way she went with anyone willingly, especially leaving her shoes and her purse, no. Where is a teenage girl going without her shoes and her purse? We knew right then that something was very, very wrong.”

For one resident of East Brunswick, she believes Belt’s murder may be related to an incident she experiences growing up. In the summer of 1975, the same summer that Belt disappeared, Barbara Robba Dipierro, then 8 years old, was riding her bike.

“I would go out first thing in the morning and ride my bike up and down the street.” She said she was approached by a man who attempted to drive her off the road, and tried to talk to her. “He wanted me to go with him some place. He said he wanted to take naked pictures of me. It scared me,” she recalled.

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Dipierro says the man was in his late 30s or early 40s with a small build, and was driving a car filled with feminine hygiene pads. Despite this encounter, no arrests or clues have come about. But her friends, family, and former classmates continue to remember her.

Hali Figueroa was Belt’s neighbor. At the time she disappeared, Figueroa was 10 years old and lived next door to Belt’s family. “Where we lived was very rural. It was not common to have neighbors. It was exciting to have someone to walk over to and do something,” she remembered. “She babysat my brother and I, and we used to ride bikes with her. We’d go around the Cranbury Road block. We used to ride our bikes everywhere. We enjoyed her company. She was kind to me.”

Her classmates also remember Belt at reunions. During the 40th high school reunion in 2016, they discussed the unsolved murder and remembered their classmate.

“The loss of Betty rattled everybody. Nobody who has their life touched by something like that is ever the same. Whether you think you are okay, or not, you’re not... I think it was just kind of disbelief for all of us. And we were also a little scared because we also had ridden bikes and walked around the same area. So, at first you’re sad and horrified and then you think, ‘Oh God, it could have been me,’ and then you feel guilty for thinking that,” Lenz recalled.

According to Lenz, the Belt family moved a few years after Betty’s disappearance, but the death of her friend remains on her mind constantly.

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Samantha Maffucci is an editor for YourTango who focuses on writing trending news and entertainment pieces. In her free time, you can find her obsessing about cats, wine, and all things Vanderpump Rules.