A Horwich high school sent a warning to parents after two alleged incidents of indecent exposure in the area of Chorley New Road.
St Joseph's RC High School sent the warning to parents this week after the second of the two alleged incidents on Sunday (May 12).
The message said the allegations of indecent exposure were of a man exposing himself to young girls on two occasions in four days in the area of Chorley New Road around Stocks Park and Station Park.
The message said: "We are aware of an adult male for the second time in four days exposing himself to young girls around the Stocks Park/Station Park areas.
"Please speak to your children about their safety whilst out on the streets."
Tony McCabe, the headteacher of St Joseph's RC High School, said the school was working with Greater Manchester Police but according to a spokesperson for the force the man was "a known nudist".
This is not, in itself, an offence according to the spokesperson for the force.
Mr McCabe said: "We worked with the police who acted swiftly and we are not aware of any further incidents.
"Parents were informed so they could speak to their children and ensure they were equipped to make good choices to keep them safe."
This article was written by Jack Tooth. To contact him, email jack.tooth@newsquest.co.uk or follow @JTRTooth on Twitter.
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