Sussex Police are still appealing for information following the incident on 21 October.
A teenage girl was walking through Clair Park late in the afternoon, from the Oathall Road direction when a man approached her in a wooded area.
The man was described as being either black or of mixed ethnic background and wearing a black hooded top and black jogging bottoms.
Detective Chief Superintendent Karrie Bohanna said: “This was a highly distressing incident, and the victim is receiving support from our officers.
“We are pursuing a number of lines of enquiry, and since this report was received, officers have been carrying out high visibility patrols in the area.
“But we are appealing for witnesses or anyone in the area at the time who may have seen something suspicious to come forward.
“This also includes anyone with CCTV, doorbell, dashcam or mobile phone footage in the area at the time who has not already reported this to us.
“The victim described that it was still light outside, this incident happened at a time when lots of people may have been in the area, so we are urging people who may have information to come forward.”
Information can be reported to Sussex Police online or by calling 101 and quoting Operation Oakland.
Ashdown Radio Sport
Charity supports with digital activities and online groups
Residents Reminded to Save the Dates for This Year’s Summer Celebrations
Western Road Recreation Ground to Become Home of New Town Beacon
Mims Davies MP joins RSPCA urging the Government to publish timeline for implementing new Animal Welfare Commitments
Vehicle seized by police in Eastbourne during patrol around town
East Grinstead primary school teacher charged with sexual assaults
Crowborough Birthing Centre 'closed until May' amid review