Police and scientists working to find the remains of a girl who disappeared nearly 60 years ago are to begin digging at a new site later this year.

Moira Anderson was 11 when she disappeared from her home in Coatbridge, North Lanarkshire, in February 1957 while running an errand for her grandmother.

In 2014, prosecutors took the unprecedented step of announcing that bus driver and convicted paedophile Alexander Gartshore, who died in 2006, would have faced prosecution for the girl's murder if he were still alive.

The Crown Office enlisted the help of forensic soil scientist Professor Lorna Dawson in 2015 as part of efforts to find Moira's remains.

After the discussion of ground reports, the Crown Office said further progress has now been made in pinpointing the areas where the search should be concentrated.

The search area has not been confirmed but it was reported last year that Ms Dawson had identified a site north of Coatbridge where a farm worker reported an empty bus blocking a lane on the night the girl disappeared.

Preparatory work is to start in the coming weeks with digging to begin in the autumn.

Detective superintendent Pat Campbell said: "At the request of the lord advocate, Police Scotland has been working with a number of subject experts from across the UK, including Professor Lorna Dawson, Hutton Institute, Aberdeen, to consider a number of potential sites within the Lanarkshire area which may be linked to the disappearance of Moira Anderson in February 1957.

"This work is presently ongoing and a detailed report regarding search options will be submitted to the Crown Office for consideration in the near future.

"The ultimate objective is to one day recover Moira's remains and to bring closure to the family of Moira and the community of Lanarkshire."

A plot in Old Monkland Cemetery in Coatbridge was previously searched by experts but failed to find Moira's remains.

Police had been investigating the possibility that Gartshore dumped the youngster's remains in the grave of an acquaintance called Sinclair Upton.

Lord advocate Frank Mulholland QC said "good progress" is being made in preparing for new searches.

"I instructed the investigation into Moira Anderson's disappearance to remain open in the hope that one day her body may be discovered and her family be given the closure they deserve," he said.

Ms Dawson, who runs a lab dedicated to forensic soil science, has worked on dozens of cases from around the world and helped bring World's End killer Angus Sinclair to justice.

She said: "We have been considering potential locations and their physical characteristics, and developing, together with Police Scotland, a search strategy combining geographical and intelligence-led information."