The arrests of at least seven Mexican drug traffickers at Narita airport since December have prompted police and customs authorities to raise their guard against illegal drugs, investigative sources said Saturday.
Some of the alleged traffickers, which were male and female, tried to smuggle the drugs in as liquids contained in shampoo bottles, the sources said.
About 17 kg of drugs, which were estimated to have a street value of ¥1 billion, have been discovered and confiscated by the airport in the past two months.
While drugs from Mexico, a major production base, are smuggled mainly to the United States, the traffickers are also believed to be targeting Japan as a market because they can fetch higher prices in Asian countries, the sources said.