Ten people have been arrested and $10.2 million in assets seized in the final operation targeting Auckland's high-end money launderers.

Police executed twelve search warrants across the city as the final stage of Operation Ida on Wednesday morning.

Four properties and three vehicles, worth over $10 million have been seized in St Heliers, Kumeu and New Lynn.

The contents of 23 bank accounts, cash, high value items and cryptocurrency wallets, worth $1 million, have also been seized. This includes approximately $200,000 worth of jewellery.

Police have laid a raft of serious charges including money laundering, obtained by deception and possession of methamphetamine for supply.

Wednesday's announcement follows two earlier instalments - operation Brookings and Operation Martinez - both terminated in late 2020.

The three operations have seen in excess of $21 million seized by police, 28 people charged and 103 charges being laid.

Detective inspector Lloyd Schmid of the financial crime group says the three operations are a culmination of more than a year's worth of investigation.

"These investigations focused on the activities of semi-legitimate businesses that we allege were engaged in a staggering amount of money laundering," Schmid says.

"Police will allege that those funds being laundered were helping to fund the importation of illegal drugs into New Zealand.

"Our enquiries to date indicate that funds were being laundered and set offshore by those involved in this operation to settle payment for illicit drugs and other illicit commodities being sent to our country."

Detective Schmid says this serves as a warning to offshore drug dealers.

"Police are no longer just targeting the importation of the drugs, but increasingly we will be targeting the money trail which funds it as well," he says.

"In the case of Operation Ida, we have investigated a money laundering syndicate operating in Auckland, with a foreign exchange business allegedly as a front for their illicit activities.

"Money laundering is not a victimless crime and while this may appear like money simply being passed around, it actually represents immeasurable harm that is being imposed on our communities."

Police acknowledge the Department of Internal Affairs and a number of major financial institutions that have assisted them throughout this investigation.

Ten people - 9 men and one woman aged 32 to 70 years - were arrested on Wednesday.

They are due to appear in the Auckland District Court on March 18 and 23.