On Aug. 7, 1972, 16-year-old high school student Jeannette DePalma told her mom she was going out to visit a friend.

When she didn’t return that evening, her worried mother called the police, who discovered she never made it to her friend’s house.

Six weeks later, a dog walking in woods near Jeannette’s home in Springfield, New Jersey, ran back to its owner with a badly decomposed arm.

The grisly find led to police discovering the teenager’s body nearby — and sparked a mystery embroiled in rumors of witchcraft and Satanic rituals, which remains unsolved to this day.

Jeanette’s body was found on a ridge known as The Devil’s Teeth and local witnesses said it was surrounded by a series of strange, occult objects with the remains of dead animals hanging from nearby trees.

Although wildly different accounts exist of the murder scene, the most consistent detail was that the body was inside a coffin-shaped structure made from fallen branches and logs, with several makeshift crosses around it.

Rumors of black magic and Satanic cults were rife and some locals blamed a coven of teenage witches who had vowed to abduct and kill a child.

The post-mortem failed to quash the rumors, as the exact cause of death could not be determined and a likely cause was listed as strangulation.

A toxicology report found no trace of drugs but a high level of lead, which was also unexplained.

Two weeks after the body was found, local papers published articles “confirming” Jeanette’s death was due to witchcraft, citing local evangelist and family friend Rev. James Tate.

As the teen coven began to become the accepted story in the local community, police arrested a homeless man who had been staying in the area, but he was soon released and cleared as a suspect.

With no more leads, the police closed the case until the late 1990s, when Mark Moran, from the magazine Weird NJ, decided to take a look.

He found the police had lost or destroyed most of the files and that locals he approached seemed too frightened to talk about the case.

After publishing an article, Moran received a flurry of anonymous letters offering chilling information about Jeannette’s murder.

One said: “I was a young teenager when the discovery of Jeannette DePalma happened and lived in the next town.”

“About two years prior, there was much talk in my school about a cult in the surrounding area. They were known as The Witches.”

“They must have let it be known in the area that they planned to kill a child on or about Halloween, either by kidnapping and sacrificing them or by poison. I remember being anxious about this because I went trick-or-treating in those days.”

Another letter, from a relative of a local policeman, read: “When the dog brought the arm home and the search for the body started, they found arrows carved in the trees that would lead you to the body.”

“All around her body were dead animals tied to trees with string and some in jars. Shortly thereafter there were reports of animals being mutilated and hung in the same fashion in the Watchung Reservation, which is also very close to the scene of the crime.”

“The Watchung Reservation or the ‘Res’ has been reported to be the center of devil worship activity for years.”

Some believe that Jeannette’s death was the work of a serial killer, who struck again in 1974 in Montvale, NJ, where the bodies of two young girls were found in the woods.

They had been beaten, sexually assaulted and strangled.

Their killer was never found, but many have dismissed this theory as there was no suggestion of a sexual assault on Jeannette.

With most of the police files gone, it seems the mystery of Jeannette’s murder will never be solved.