Police in Doncaster would like to appeal for witnesses following a suspicious incident in the Toll Bar area between 12.30pm and 1pm on Saturday,15 December.
It is believed that an unknown man approached two girls aged six-years-old and nine-years-old in the park on Northfield Avenue. He is believed to have left the area in a large blue van with sliding doors, with a ladder on the roof.
DS Maggie Hawksworth said: "Police are in the early stages of establishing the details of this incident. Whilst enquiries are ongoing, we would like to appeal for anyone with information about the vehicle to come forward and ask that residents are extra vigilant by reporting any suspicious behaviour."
Anyone who may have seen the man in the park or the vehicle in the area is urged to contact South Yorkshire Police quoting incident number 575 of 15 December.