The girl reported being approached by an unknown male, as she played on a cycle path to the rear of the South Queensferry Bowling Club between 1.30pm and 1.45pm on Friday.
It has now been confirmed that the victim was indecently assaulted and detectives are pursuing various lines of investigation to trace the suspect.
He is described as white, high school age with hazel brown-coloured hair that was swept forward and wearing dark bottoms, a blue round neck t-shirt with white lettering and had a temporary tattoo on one of his hands. He was also in possession of a black and blue rucksack.
Detective Inspector Julie Marshall from Edinburgh’s Public Protection Unit said: “Over the weekend we have been conducting further investigation to establish the full circumstances surrounding this incident and we are now confident that the young victim was indecently assaulted.
“We are eager to speak to anyone who remembers seeing any suspicious activity in the wooded area around the cycle path on Friday afternoon and those who believe they may have information relevant to this inquiry should contact police immediately.
“I would also ask that anyone who recognises the description of the suspect to come forward. Local residents are urged to think of anyone they know of in the local community who may have a temporary tattoo on one of their hands and who also owns a black and blue rucksack.
“These are distinctive traits and I’m confident someone knows the individual responsible for this attack.”
Chief Inspector James Jones, Local Area Commander for North West Edinburgh said: “Thankfully, incidents such as this are incredibly rare, but we recognise the impact they can have on the local community and as such we will have high-visibility patrols operating in the area around the woodland and cycle path while the investigation continues.
“If you have any information and wish to pass it to the police, please speak with one of the officers on patrol or contact us on 101. Alternatively, you can make an anonymous report to the charity Crimestoppers on 0800 555 111.
“South Queensferry is a very small and close-knit community and I have no doubt that one of our local residents may have the vital information to help us solve this crime.”