An 18-year-old man and a 15-year-old girl have been arrested in Hong Kong for suspected drug trafficking and possession after police seized narcotics worth about HK$278,000 (US$35,780) including ketamine and “space oil” vape cartridges.

Police said on Wednesday that the pair were arrested at a flat in Yau Ma Tei on Monday.

Officers raided the home on Man Ying Street after gathering information in an investigation conducted by a Yau Mei Tei special squadron and uniformed patrol officers, the force said.

Police discovered about 475 grams of suspected ketamine and 121 suspected vape cartridges containing liquid etomidate, with a combined street value of HK$278,000.

Etomidate is a powerful anaesthetic that has gained notoriety in recent years as a common main ingredient in space oil, a recreational drug that has rapidly become popular among youngsters. The narcotic is often used in e-cigarette capsules.

The operation also uncovered a cache of suspected drug packaging tools.

Police said the arrested pair were facing drug trafficking and possession charges, and remained in custody as officers continued investigations.