Inspector Richard Quinn, from Cumbria Police said:
"The dog is currently in our care. Because a child is involved we need the full facts before we can determine what should be done with it.
"At this stage we haven't had an opportunity to interview the parents but we believe this may have been a terrible accident."
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Kerrie Gosney brings you Sunday night's forecast
The party leader said her MPs may be in a position to act as deal makers - and they would refuse to allow an exit from the EU.
Rain spreading east Sunday. Decent day on Monday, more changeable thereafter