Police divers are due to begin investigating five “areas of interest” in the search for a North Lanarkshire girl who disappeared 60 years ago.
An operation began last week to scan a section of the Monkland Canal in an effort to locate the remains of 11-year-old Moira Anderson.
She left her grandmother’s house in Coatbridge on 23 February 1957 to go to the shops but never returned.
Convicted paedophile Alexander Gartshore is suspected of her murder.
The first phase of the operation focused on a 170m (185 yards) stretch of canal at Carnbroe. Although it is 3.5m (11.5ft) deep, around 2m (6.5ft) of that is silt.
The team were joined by leading experts including soil forensic expert Prof Lorna Dawson and forensic anthropologist Prof Sue Black.
The search involved the use of ground-penetrating radar, sonar scanning and magnetometry, which identifies magnetic anomalies within the water and silt layer of the canal.
Police Scotland said the techniques resulted in the identification of “five distinct areas of anomalies”.
Divers from its marine unit will begin a more detailed investigation of those areas later, identifying and removing any relevant items.
Bus driver and convicted paedophile Alexander Gartshore, who died in 2006, is suspected of murdering Moira and disposing of her body.
When she left her grandmother’s house during a heavy snowstorm, she boarded a Baxter’s bus that was driven by Gartshore.
Later that year, he was jailed for raping a 17-year-old babysitter.
In 1999, convicted child abuser James Gallogley named his former friend Gartshore as Moira’s murderer.
Gartshore’s own daughter Sandra Brown was convinced he was the killer and campaigned to have him charged.
In 2014, prosecutors announced that Gartshore would have faced prosecution for the schoolgirl’s murder if he were still alive.
A previous search has focused on the theory that he may have buried her body in Monkland Cemetery, in the family plot of an acquaintance, but an excavation in 2013 found nothing.
The latest searches were prompted by a sighting, reported in 1957 but not followed up, of a man carrying a large heavy sack towards the canal.