The FBI and Burlington County authorities are hoping an enhanced version of an audio clip can help solve the mystery of what happened to a 14-year-old girl who disappeared in 1974.

Margaret Ellen Fox was last seen getting off a bus in Mount Holly, where she was to meet someone who had answered her ad for a babysitting job. She had traveled from her home in Burlington City, about 7 miles away.

Hours later, her parents received a call from a man who appeared to be asking for $10,000.

"$10,000 might be a lot of bread, but your daughter's life is the buttered topping," the man says on the short clip.

FBI officials say that they hope that the renewed effort in the case will bring about some leads.

“The FBI has a long memory,” Assistant Special Agent in Charge Joseph Denahan said in a statement. “The community we serve has our solemn promise that we will pursue all viable options in the interest of delivering justice.”

The FBI is offering up to $25,000 for information leading to an arrest or conviction in the case.

Anyone with information about Fox’s disappearance is asked to call the FBI Newark Field Office at 973-792-3000 or Burlington City Police Department at 609-386-0262, extension 211.