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Six puppies and their mother were dumped in a swiftly flowing Northland river in what an SPCA official says was an act of 'premeditated cruelty'.
SPCA senior inspector Jim Boyd, of the Bay of Islands, said the dogs were thrown over a bridge into a river at Taheke.
The mother swam to to shore, but at least three pups died when they plummeted over a 20m waterfall. Two others were rescued, but had to be euthanised.