Japanese authorities at Haneda Airport in Tokyo detained five drug smugglers attempting to smuggle approximately 5kg of cocaine valued at ¥120 million (RM3.1 million), which was hidden under the insoles of their shoes.

The group - four men and one woman, all Malaysians - were intercepted during a customs inspection upon arrival in Japan. They had successfully bypassed security checks while departing from the Kuala Lumpur International Airport (KLIA).

Customs officials grew suspicious of one of the suspects after noticing that the soles of his shoes were unusually thick, Fuji News Network reported.

A search revealed cocaine hidden under the shoe insoles of two of the suspects, prompting officers to identify three other individuals believed to be travelling with them.

Japanese news outlets reported that the three others had also hidden cocaine using the same method.

According to TBS News DIG, each suspect was carrying roughly 1kg of cocaine, with 500g hidden under the insoles of each shoe they were wearing.

One of the five suspects was reportedly offered a fee of RM8,000 via the Telegram messaging app to carry the drugs overseas.

He was also provided with a pair of shoes designed to conceal the illicit substances.

Meanwhile, NHK reported that four of the suspects admitted to the charges during interrogation, while a 25-year-old woman denied them.

The woman claimed she was unaware that the packages she was carrying contained cocaine.

Local media reported that the Tokyo Metropolitan Police are investigating whether the suspects were recruited by a Malaysia-based syndicate involved in international drug trafficking.

Airport security enhanced

This latest development comes on the heels of the Home Ministry reportedly saying it would undertake full physical checks on passengers and baggage for flights departing from KLIA to destinations classified as high-risk, as part of measures to tighten airport security controls.

Home Minister Saifuddin Nasution Ismail said the classification of high-risk destinations was made based on data and smuggling cases, including several destinations such as Indonesia.

"For outbound flights from KLIA, we conduct a physical pat-down, head-to-toe screening on individuals and also a full baggage inspection," Saifuddin (above) said previously.

Discourse on airport security has heightened after two Malaysians were arrested in Indonesia in separate drug trafficking cases.

One of the suspects is a Malaysia Airlines pilot who was detained for possession of over 70,000 ecstasy pills and 2.7g of methamphetamine, while the other is a 22-year-old who was arrested for allegedly attempting to smuggle 990g of methamphetamine and 1,089 ecstasy pills.