"This investigation is at an early stage, however we have nothing to suggest that there is any threat to the wider community.
"I would urge anyone with information about the deaths to contact police on 101."
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Kerrie Gosney brings you Saturday night's forecast
Showers becoming heavy and thundery Saturday afternoon. Drier for a large part of Sunday
Robert Hodgson, from Stanley, County Durham, committed the offences on the girls, aged as young as five or six, up to the age of 13.