Police would not speculate on the role Harries played in the operation because the matter was before the courts.
In the early-morning raid on Wednesday, police arrested a man leaving the property carrying one bag with 952g of P worth more than $800,000 and another with $157,000 cash.
A further search of the large rural property led police to discover P and 21kg of the precursor material Contact NT - with a street value of more than $900,000 - which could be used to manufacture a further 4.5kg to 6.5kg of the illegal drug.
P sells for between $700,000 and $1 million a kilogram.
A loaded pistol was also found hidden in a vehicle and another loaded military-style semiautomatic gun was found near the P laboratory.
Two men and a woman were at the property.
Searches were later carried out in Waitomo and Cambridge and P, cash and an unknown liquid were uncovered from the Cambridge property.
Harries and two men aged 56 and 53 and a 28-year-old woman were arrested as a result of the searches.
Police were yesterday still searching the Oruanui property, described as the "pinnacle" of the operation, and expected to uncover more.
The discovery of drugs, cash and firearms is expected to curb organised crime in the Waikato and the Bay of Plenty.
Mr Keall said the bust, significantly bigger than the Newcastle Rd one in Hamilton in August 2007 and the second-biggest, if not the biggest operation to be uncovered in New Zealand, would make a large dent in organised crime in the central North Island.
"The link between methamphetamine and other drug offending and serious violence offences, intimidation, burglary and theft has been well documented and researched.
"With a seizure of this size and apprehension of the associated people we would expect a significant downstream reduction in that type of offending in the Bay of Plenty and Waikato policing district," Mr Keall said.
"When [police staff] discussed it this morning there was only one other lab that came up that was possibly comparable, given the proven production of the lab and the methamphetamine we've already seized, other methamphetamine we know is there and the huge volume 21kg of precursor present."
He said the laboratory at Oruanui was the centre of the operation but police would be carrying out other investigations as a result of other information they had collected.
"We are very buoyed by the success, however given the intelligence we had received, given the indication from our investigation prior to actually executing the search warrant we knew it was likely to be a significant find."
About 80 officers were involved in Wednesday's searches but a smaller core team had been investigating for some time.
Harries appeared in Taupo District Court on Wednesday facing a number of charges including possession for supply of P, conspiring to deal P and using and producing and manufacturing.
He will reappear next month.
A 56-year-old also appeared in the Taupo District Court on charges relating to the manufacturing and supply of P.
A 50-year-old man appeared in the Hamilton District Court on three P charges and a 28-year-old woman arrested at a Waitomo property also appeared on similar charges.
