Man charged with the murder of missing Sydney schoolgirl Quanne Diec

A man has been charged with murder almost two decades after the disappearance of Sydney schoolgirl Quanne Diec.

The 49-year-old man attended Surry Hills police station on Sunday afternoon to speak to detectives.

Authorities hand out photos of missing school girl Quanne Diec in 1998. Photo: Dean Sewell

He was later charged with murder and refused bail. He is due to appear in court on Monday.

It is understood he is not related to Quanne, 12.

Then Premier Bob Carr announced a reward with Quanne's parents, Anne and Sam, and her sister Tina in 1998.  Photo: Julian Andrews

Quanne went missing in 1998 after she left her family's home in Granville to go to school.

She was intending to catch a train from Clyde to Strathfield but did not arrive at school and was never seen again.

Quanne was feared to have been kidnapped early on in the investigation but her disappearance was not reported to police for about 10 hours because the school believed she was probably sick at home.

In 1998, then premier Bob Carr offered a $200,000 reward for any information leading to Quanne's location or anyone involved in her disappearance.

Quanne Diec. Photo: Peter Rae

Her body has never been found.

Investigators initially believed the remains of a young girl found in a suitcase in South Australia in 2015 may have been Quanne's. They turned out to belong to Khandalyce Pearce.

Detectives from Rosehill Local Area Command, with assistance from the State Crime Command's Homicide Squad, recently opened Strike Force Lyndey to investigate the matter again.

Rosehill Superintendent Scott Whyte will address the media at 9.30am.

"The Diec family have been informed of the arrest and have requested their privacy be maintained," police said in a statement.

More to come