Northumbria Police said that they believed a number of children tried to rescue one of the girls who died in the River Wear, before a second got into difficulties and died.
Supt Veitch said Chloe, who was from Shiney Row, near Sunderland, got into the water of her own free will.
Chloe went in first, Tonibeth and others went in to help her.
Tonibeth got into difficulties and so have the others.
The emerging picture is that she went in to keep cool.
I think there's a lot of children who were trying to effect a rescue.
The officer said the children who survived were traumatised and receiving counselling.
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