A 22-year-old who served as the acting national commander of the Comancheros has been found guilty alongside others of conspiring to import a massive 600kg haul of methamphetamine - estimated to be worth roughly $90 million - into New Zealand from South Africa.

Jurors in the High Court at Auckland returned guilty verdicts against Seiana Fakaosilea, as well as co-defendants Jie Huang and Richard Pelikani, this afternoon. They had been deliberating since Tuesday.

The defendants were arrested in 2020 at the end of Operation Cincinnati, a months-long police investigation into the distribution of meth and ecstasy by the Comancheros in Auckland and the Rebels gang in Christchurch.

Investigators had obtained a High Court judge's permission to bug suspects' phones and place listening devices in vehicles. In March that year, Fakaosilea was driving through Auckland in his Toyota Corolla when authorities listened in on a conversation between him and Huang during which "600 keys" were mentioned.

Although their conversation was jilted and in code, the two were discussing plans to import 600kg of methamphetamine from South Africa and an unknown amount from Fiji, prosecutors argued.

Police never intercepted any such shipments. But just planning such a scheme - regardless of whether it was carried out - is enough for a conspiracy conviction, prosecutors Robin McCoubrey and Ben Kirkpatrick told jurors.

Richard Pelikani has been found guilty of conspiring with others to import 600kg of methamphetamine from South Africa. Photo / Brett Phibbs

Jurors couldn't reach unanimous verdicts for any of the conspiracy charges against the three defendants, but 11 were able to agree on a guilty verdict, which was enough for a conviction.

In addition to the South Africa meth conspiracy and the Fiji meth conspiracy charges, Fakaosilea was found guilty of one count of possession of methamphetamine for supply. Jurors unanimously found him not guilty of two other counts - a separate possession of meth for supply charge and a supplying meth charge.

Huang was found guilty of both conspiracy charges along with a supplying meth charge, but he was acquitted of attempted aggravated robbery. Authorities had accused him of instructing Comancheros members to rob an Airbnb rental where drugs were being sold. The robbery was intended as a "tax" for using Huang's and the Comancheros' names, but it was thwarted after detectives listening in on the conversation intervened, prosecutors had alleged.

Defendant Taniela Mafileo was found not guilty of two methamphetamine-related charges but pleaded guilty to other charges before the trial began. Photo / Brett Phibbs

Pelikani was convicted of the South Africa conspiracy while a fourth co-defendant, Taniela Mafileo, was acquitted of two meth-related charges.

However, all four men along with 10 others had pleaded guilty to various other charges in the days before the trial began so Mafielo will rejoin his co-defendants in the courtroom dock at a later date.

Justice Neil Campbell set a provisional sentencing date for next month for all 14 defendants, but he said he expects dates to change as lawyers determine who should be grouped together and sentenced at the same time.