Parkrun runners pelted with stones by teenagers at Sloughbottom Park in Norwich
People taking part in a weekly Parkrun were pelted with stones by youths.
A 12-year-old girl suffered bruising and a man sustained swelling to the head in the incident at Sloughbottom Park in Norwich, said police.
Norfolk Police were called to the park on Drayton Road on Saturday, 5 November to reports of young people throwing stones.
The youths ran away and have yet to be identified.
Parkrun is a free 5k run which is held in hundreds of park locations around the UK at 9am on Saturday.
Police are now appealing to anyone who was at the event and may have witnessed it to come forward.
Anyone with information should call police on 101.
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