Pictures from Hartfield Square park on Tuesday (July 19) showed a number of Sussex Police officers, with scenes of crimes officers (SOCO).
Sussex Police said officers responded to a call from a member of the public about a ‘distressed woman’ in Hartfield Park, around 5.15am.
A spokesperson added: “Officers attended the scene where the woman reported that she had been raped.
"There is likely to be an increased police presence in the area while the investigation continues.
"This is believed to be an isolated incident. The victim has been receiving support from specially trained officers.
"An 18-year-old man has been arrested on suspicion of rape and remains in custody at this time.”
Eye-witnesses saw detectives scouring the recreation area, and nearby roads, on Tuesday afternoon.
The park, by The Avenue, is home to a children’s playground, and was closed by emergency services.
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Forensics investigate serious incident in Eastbourne's Hartfield Square Park. Photo: Dan Jessup Photo: Dan Jessup
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Forensics investigate serious incident in Eastbourne's Hartfield Square Park. Photo: Dan Jessup Photo: Dan Jessup
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Forensics investigate serious incident in Eastbourne's Hartfield Square Park. Photo: Dan Jessup Photo: Dan Jessup
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Forensics investigate serious incident in Eastbourne's Hartfield Square Park. Photo: Dan Jessup Photo: Dan Jessup