Police were called at 9.41am on Wednesday (Jul 14) and responded to reports of concern for the safety of a 17-year-old girl, following an incident in Elmfield Park, Bennetthorpe, near Doncaster.
It is reported that as the teenager walked through the park, she was approached by an unknown man who grabbed her from behind and pushed her to the ground.
The teenager managed to fight the man off, before leaving the park.
A large-scale investigation is underway to identify and locate the offender, with significant resources deployed to the area.
The offender has been described as white in his mids 20s and around 5ft 11inches tall. He was wearing a black face mask, black hoodie and bottoms and dark blue gloves. He spoke with a strong accent.
Superintendent Simon Wanless said: “I know this incident will be extremely distressing and concerning to the local community, I would like to reassure you that we are taking every step possible to identify the individual involved.
“We have deployed extensive resources and the park is currently closed to the public whilst we carry out our enquiries.
“You will see a heightened police presence throughout this afternoon and into the evening, please go and speak to officers if you have any concerns, they are there to help.
“The victim is being supported by specially trained detectives.
“I would like to urge anyone who was in the area prior to or during the time the incident is alleged to have taken place, to contact us immediately.”
The incident number is 228 of July 14.