The pair were arrested at a residence on Soi Cherng Talay 14 on Monday (Nov 3), Cherng Talay Police reported.
The pair were named as Nigerian national Kenneth Sibowo Nat, 37, and Thai national Nitida Karaket, 32, from Udon Thani.
During the operation, police seized 33 items of evidence, including 6.07 grammes of cocaine, 6.05g of crystal meth, 9.36g of ketamine and ecstasy tablets in various colours and shapes.
Also seized were drug packaging materials, digital scales, four mobile phones and a black Toyota Yaris Ativ registered in Bangkok.
Officers also confiscated several bank books and an ATM card in the woman’s name, believed to be linked to drug-related financial transactions.
Police confirmed that the woman tested positive for cocaine use during an initial drug screening.
Both suspects were charged with possession of Category 1 and Category 2 narcotics with intent to sell, as well as possession of a Category 2 psychotropic substance (ketamine).
The Nigerian man faces additional charges of staying in the Kingdom after his visa expired, while the Thai woman faces a further charge of using a Category 2 narcotic without permission.
The pair were taken to Cherng Talay Police Station for further questioning and legal proceedings.
Police said the arrests were part of a week-long operation targeting drug-related offences from Oct 29 to Nov 4. The operation was part of a continuing crackdown on drug trafficking in Phuket, in line with the province-wide campaign to suppress crime and improve public safety, Cherng Talay Police noted.