BBC crime correspondent Stephen Cape: Unbelievable grief of parents

The anniversary on Tuesday will be marked by a news conference where the family will once again appeal for help.

And for the first time a substantial reward will be offered for information.

It is believed Melanie, 25, was killed and the body hidden. She is just one of thousands of people who go missing every year. Most are found, but some are never located.

A massive police hunt was launched after Melanie disappeared.

Left in limbo

But even exposure on the BBC TV programme Crimewatch failed to unearth enough evidence.

Her parents say part of them died when their daughter disappeared.

Melanie is classed as a missing person, but her father Stephen believes she was murdered and appealed to those that know who committed the crime or those that were shielding the murderer.

He said: "They have caused unbelievable grief to many people. They can undo that now and at least give us the right and dignity to bury Melanie."

Sophie Woodward from the National Missing Persons Helpline said most of those that go missing eventually turn up.

She said: "For a family left waiting for news it is agonising. They are left in limbo and we are here to support them."