Police and Customs have seized about 200kg of methamphetamine after the huge haul was discovered at the Port of Tauranga.

The four men arrested all had associations with the Mongrel Mob, Comancheros and the Filthy Few, police said on Saturday.

Customs officers became aware of a suspicious concealment on 11 December after a routine X-ray of a container.

"At about 3pm two men entered a restricted area and forced entry into the container. Police were alerted as the men loaded the suitcases into their car," police said in a statement.

"The vehicle left the port driving recklessly and at speed through heavy traffic on the East Link Toll Road towards Whakatāne."

The vehicle was stopped using road spikes. The two suspects fled on foot, but were quickly apprehended.

Both men, 28, have been charged with burglary, possession of methamphetamine for supply, failing to carry out obligations in relation to a computer search, and possession of instruments for burglary.

They were remanded in custody, and will reappear in Tauranga District Court next year.

Search warrants a week later resulted in two more men being arrested and charged with "a number of offences, including importation of methamphetamine".

Police said an "insider threat" the port had been removed.

"It is believed members of this criminal operation may have been operating from within the port for some time."

The methamphetamine seized was enough for 10 million doses, Detective Inspector Albie Alexander said, and had a street value of about $75 million.

"This illustrates another example of the continuing cooperation and strong partnerships we have with Customs and our local and domestic partners in targeting criminal activity at our borders and in the community."

Customs investigations manager Dominic Adams said there had been an 'increase in legitimate imports being targeted by overseas criminal groups who conceal illicit drugs within freight containers or container contents".

"Our increased port and maritime presence is helping us face this threat."

-RNZ