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The landlord of a Hamilton house where police say they found one of New Zealand's biggest methamphetamine labs says scientific tests challenge the claims.
Kerry (Rocky) O'Rourke said he became sceptical of the size of the P lab operation after he paid for forensic tests on the house. The tests had determined mercury levels were lower than in many working environments.
Spokesman Andrew McAlley said police were still awaiting ESR results and would not release anything further until the prosecution had been completed.