The mystery murder of an 11-year-old girl has been solved after the discovery of new evidence, police say.

Melissa Ann Tremblay was found dead in a rail yard in Massachusetts, US, one day after she was reported missing in 1988.

She had been stabbed and run over by a train, with footprints and blood discovered nearby suggesting a struggle had taken place.

Marvin C. McClendon Jr., a 74-year-old former correction officer, was arrested over her murder on Tuesday.

Police say evidence retrieved from the victim's body played a key role in the arrest in Bremen, Alabama.

Essex District Attorney Jonathan Blodgett said his cold case unit had been trying to solve the murder since 2014.

The Sun reports that McClendon Jr. had been a 'person of interest' in the case for some time.

He said: "The evidence led us to him. It (the evidence) will be spelled out in the arraignment.

"I can’t even express how gratified we are in this office that we are able to pursue justice for any family.

"And it is extremely gratifying that after all these years of never giving up, we believe we have the right suspect."

Melissa went missing when she visited a social club with her mum and her mother's boyfriend on September 11, 1988.

She vanished after going outside to play while the adults stayed inside the club in the city of Lawrence.

The youngster was reported missing and her body was found in the rail yard the next day.

McClendon, who worked in carpentry at the time, lived in the nearby town of Chelmsford but had multiple ties to Lawrence, where he attended the Seventh Day Adventist Church , Mr Blodgett said.

According to Boston.com, Mr Blodgett added: “This case has been pursued, I would suggest to you, in a very diligent fashion since 1988, since we discovered her body."

Leslie Malone, McClendon's second cousin, said the suspect 'was not a nice person' and had been 'a thorn in her side' since moving into a home he built in Bremen in 1988, the Boston Globe reports.

Ms Malone added: "He made a lot of threats, not like killing me or anything but . . . just kind of idle threats.

“He was just that way.”

Mr Blodgett added that Melissa's aunt and cousin had been informed of the arrest.

Her mum, Janet Tremblay, reportedly died aged 70 in 2015.

Melissa's childhood friend Andrea Ganley reacted to the news of the arrest by saying she 'never gave up hope'.