Detectives working on the case say they have uncovered “several items” including women’s clothing in a search of woodland near Roberton.
The naked body of Ms Caldwell, 27, was discovered in a ditch in isolated woodland in Lanarkshire by a dog walker in May 2005.
The Sunday Mail newspaper reported that other “significant items” had been found which were being forensically examined to determine if they belonged to Ms Caldwell.
Police have appealed again for witnesses in the hope that someone with information will come forward.
Detective Superintendent David McLaren said in the interview he was “certain there are women out there who have information that will contribute towards putting Emma’s killer behind bars”, and urged them to get in touch.
Police Scotland said the information given to the newspaper by Mr McLaren was accurate.