Airport Command and Customs Drug Investigation Bureau officers have cracked the first case in which passengers at Hong Kong airport were found to be trafficking in ketamine.

On Wednesday, Customs officers seized 5.12 kg of suspected ketamine worth $1.8 million in two cases during an anti-narcotic operation codenamed "Operation Bayonet".

They arrested two Malaysian men, aged 26 and 39. The pair will be charged with trafficking in dangerous drugs and appear in Tsuen Wan Magistrates' Courts this afternoon.

The Customs officers who stopped the men, who had arrived in Hong Kong from Kuala Lumpur, thought they looked suspicious.

A search uncovered 3.12 kg of ketamine in a concealed compartment of a piece of luggage, and another three bags of ketamine weighing 2 kg were packed in three boxes bearing food products labels.

Customs officers will liaise with overseas and Mainland counterparts to track down the mastermind.

An anticipated increase in demand for drugs during the upcoming Lunar New Year holidays triggered "Operation Bayonet". Customs officers believed dangerous drugs would be smuggled into Hong Kong from Southeast Asia to take advantage of the heavy passenger flow during the holidays.

Drug trafficking carries penalty of life in prison, $5m fine

The Customs & Excise Department will step up anti-narcotic measures at all control points to crack down on drugs-trafficking activities.