A concerned mother has urged youngsters to be vigilant after her 11-year-old daughter and two friends were approached by a man in a Derbyshire park.
The mother, who did not want to be named, claimed the man - who is believed to be in his 30s - asked the three children if they 'would like to make some money' as they took part in a treasure hunt.
He then followed the girls for a short time as they ran off.
Derbyshire Constabulary is currently investigating the incident, which happened in Shipley Country Park in Heanor yesterday.
The worried mother told the Derby Telegraph: "My 11-year-old daughter and her two friends were approached today by a man who asked if they'd like to earn some money.
"This was on the circular path near the visitors centre where they were doing the treasure hunt activity.
"The girls were very good and ran away but he followed them.
"They called us to fetch them and thankfully are safe.
"Please be vigilant and reinforce stranger danger to your kids."
The man is described as white, around 5ft 8in with a beard.
He was wearing a grey t-shirt, shorts and sunglasses, carrying a carrier bag and wearing a rucksack.
She added: "This could be innocent but it doesn't sit well with me - so I am just sending out a warning to parents."
A Derbyshire Constabulary spokesperson said: "We are looking into reports of a man behaving suspiciously on Shipley Country Park in Heanor after we received a call at around 4.20pm on Monday, July 30.
"The mother of an 11-year-old girl has expressed concern regarding a comment made to her daughter by a man near to the visitors centre at the park.
"We will be talking to the mother further about her concerns."