Police are currently carrying out a detailed search of Tandle Hill Country Park in Royton after a teenage girl was assaulted on Friday.
Two police scenes are currently in place within the park area. The first surrounding the monument and the second is surrounding the cafe by the entrance.
The scenes are expected to remain in place while specialist officers carry out a full investigation.
A spokesperson for Greater Manchester Police said: "Officers were called on Saturday, March 21 to reports of a suspected assault of a teenage girl in the Oldham area. The assault is believed to have taken place the previous day, on Friday (March 20).
"Officers will remain visible locally to provide reassurance and support the investigation."
Anyone with information is asked to contact police on 101, quoting log 2161 21/03/26.
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