Police have charged five people in Sydney over the importation of an estimated $180 million worth of methamphetamine concealed inside kayaks sent from China.

Customs allegedly found about 183kg of the illegal drug on Wednesday last week after x-raying 27 kayaks that had entered Australia.

The tests showed 19 of the kayaks contained packages with methamphetamine inside.

Australian Federal Police allowed the kayaks to be delivered to a Sydney storage facility, where they arrested four Taiwanese nationals.

Three of the men, aged 21, 30 and 35, were charged with possessing a commercial quantity of drugs and the fourth, a 28-year-old woman, was charged with drug importation.

Police later arrested a 32-year-old Kensington man at his home and charged him with attempting to import the drugs.

Customs regional director Tim Fitzgerald said the 183kg of crystal meth was found in watertight areas inside the kayaks.

There were also a number of lifejackets inside the boats that may have been put there to misdirect the attention of any searches, he added.

“It’s fair to say that any item coming into Australia can be used to hide narcotics,” he told reporters in Sydney on Wednesday.

“Previously through airports, we’ve seen narcotics concealed inside surfboards.”

Mr Fitzgerald said that in the past 14 months, Customs had found more than 1000kg of meth in liquid and crystal form.

He said the drug was a “significant problem” for border protection authorities and a significant amount came from China.

Australian Federal Police Sydney manager Ray Johnson said people accused of drug hauls of the amount found in the kayaks could expect to face around 15 years in jail.

All five people arrested over the haul will face Sydney Local Court on Wednesday.