Police have confirmed they received a report of the incident which happened at around 7.15pm in Longland Rec by Sancroft Road in Eastbourne.
Officers rushed to the scene and a thorough search of the area was carried out including a police search dog but no trace of the man was found.
The girl’s mother said on Facebook her daughter and friends had rum away from the clown character but had been left shaken up.
A spokesperson at Sussex Police said, “Police were called at around 7.15pm on Monday to a report that a man dressed as a clown was seen carrying a knife by a group of friends.
“No threats were made and the group were not approached by the man. They ran off as soon as they saw him.
“A thorough search of the area was carried out by officers and a search dog but no one matching the description was found.”
The incident came days after a cyclist was riding along a path in Golden Jubilee way and a clown jumped out of the bushes carrying what police have described as an offensive weapon.
Police are advising pranksters not to dress up as a clown and frighten strangers with a weapon after the force received numerous calls over the weekend from people feeling intimidated by the new trend.
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