A 13-year-old girl was raped after she was approached by two men in woods in Angus.
Police said the attack took place near the quarry and war memorial outside Kirriemuir.
The incident is said to have taken place in the early evening on a date between Monday January 13 and Friday March 30.
The men involved are both described as 6ft 2in with brown hair and aged between 25 and 37. They wore sweatshirts and jogging bottoms.
Police are appealing for dog walkers who use the area to come forward.
Detective sergeant Kevin Mollison said: “This was a traumatising incident for the young teenage girl and we are giving her the necessary support she needs at this time and will continue to do so.
“Our inquiries are at an early stage but we do believe it was an isolated incident.
“As part of our investigation, officers will be carrying out door-to-door inquiries in the area. We are keen to speak to anyone who may be a regular dog walker in the area and have information that could help.”
He added: “In addition, local uniformed officers will provide an increased presence in the area in the days ahead and I would encourage members of the public who have information or concerns to please approach these officers.
“Anyone with information is asked to call Police Scotland on 101, quoting reference CR/13700/20 or make a call anonymously to the charity Crimestoppers on 0800 555 111.”