Acting Deputy Commissioner of Police Halatoa Taufa told local media four male adults from Ha'alaufuli have recently been arrested in Vava'u.
Matangi Tonga reports they remain in police custody and have been charged with engaging with others in the supply of illicit drugs.
It's estimated 14 kilograms of cocaine have been seized in the outer island with an estimated street value of more than $2.1 million USD.
Last month the first cocaine packets washed up on Vava'u beaches and were handed to Tonga police prompting a extensive search operation.
Police investigations continue.