Police have arrested 19 people following a 12-month investigation into the manufacture and supply of ecstasy across New Zealand.

Police also seized about $14 million worth of assets in raids across Auckland.

More than 200 officers were involved in raiding 45 addresses across Auckland, where residential properties, several high value motor vehicles, jet-skis, a boat, pill presses and dies were seized.

Officer in charge of Operation Ark, Detective Inspector Bruce Good, said the Armed Offenders Squad assisted at two of the targeted addresses.

"We believe the syndicate we have interrupted today is responsible for the bulk of the manufacturing and supply of ecstasy in New Zealand which involves tens of thousands of pills a week going out into the market where people pay at least $40 a pill,'' he said.

"What is also of concern is that many of the pills or tablets seized comprise various mixtures of compounds, the effects of which when consumed could be fatal. Some were being manufactured on premises where rat poison was also made."

Police located eight pill presses at three locations - Onehunga, Highbrook and Albany - as well as several dies for the presses, kilos of compound ready to be pressed, tens of thousands of pills and a loaded shotgun.

Meanwhile, a warrant has been issued for the arrest of Allen Bryan Cho, 36, of Hobson Garden Apartments, Hobson St, Auckland in connection with the busts.

Police are concerned he may attempt to obtain and use false documentation to leave the country and want anyone with information on his whereabouts to contact Detective Sergeant Lloyd Schmid on 0274 746663 or call Crimestoppers anonymously on 0800 555 111.