Britain's fattest five-year-old has been taken into care after weighing in at more than 143 pounds, or at least three times the weight of what is expected of a healthy child.

Child protection experts told the Sunday Times the case was "a tragedy", expressing disbelief that action was not taken sooner by the local council.

The newspaper says the girl was seized in Newport, south Wales, in August last year weighing approximately 145 pounds – heavier than any 5-year-old of either sex recorded in an English school since 2008. Typically, girls that age weigh about 42 pounds.

Newport city council said the decision was made purely because of the girl’s obesity.

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