Customs officers in French Polynesia have made their biggest-ever single seizure of methamphetamine.

The deputy public prosecutor said they found almost 9kg of the banned drug concealed in baggage of passengers arriving in Tahiti from Los Angeles last week.

The drugs were reportedly hidden in an overhead projector and in chocolate boxes.

Four people were arrested at Faa'a International Airport while a fifth person surrendered to investigators a day later.

The prosecutor says some of them claimed they didn't know about the drugs in their luggage.

If found guilty, they could face jail for 10 years and be fined US$9 million as well as a fine corresponding to the value of the drugs.

Methamphematine sells for about $US1250 on the Tahiti black market.