After a consumption tax increase in 2014 led to a recent surge in gold smuggling cases in Japan, customs officials are stepping up their hunt for smugglers.
But with gold prices remaining at high levels, reversing the trend appears no easy job for the authorities, who are fighting to outwit smugglers in what amounts to a game of cat and mouse.
The 2014 tax increase has served as an incentive for those looking to make easy money by smuggling gold into the country and evading the tax that would otherwise be imposed.
In late May, 206 kilograms of gold bars, estimated to be worth around 1 billion yen ($9.06 million), were seized from a boat in Saga Prefecture, southwestern Japan, the largest case of illegal gold importing in the country.
Five women were arrested earlier this month for allegedly smuggling in around 30 kg of gold, worth around 130 million yen, on a flight from South Korea to Japan last December.
The possession of gold, in itself, is not illegal, which customs authorities believe helps lower the psychological barrier to smuggling it.
"We are mindful of the severity of the situation regarding gold smuggling," a government official said.
"One striking point about gold smuggling is that it has been done by air travelers...and that trend hasn't changed," the official said.
In Japan, the consumption tax, currently at 8 percent, is levied on gold when imported. But perpetrators try to evade the tax and sell smuggled gold at shops that will buy it a price that includes the tax.
The number of gold smuggling cases handled by law enforcement averaged nine a year in the nine years through June 2014. The figure then spiked to 177 in a one-year period through June 2015 and jumped further to a record 294 a year later, according to Finance Ministry data. Japan implemented a 3-percentage-point tax increase in April 2014.
Gold was mainly smuggled from Hong Kong and South Korea, with people wearing it or concealing it as souvenirs.
The Japanese Consulate General in Hong Kong now warns on its website that gold smuggling is a serious and punishable crime that involves tax evasion.
Coupled with the increased profit to be made by avoiding paying the higher tax rate, customs authorities believe relatively high gold prices are also aiding the uptrend.
"Gold has multiple characteristics," said Yuji Kameoka, chief foreign exchange analyst at Daiwa Securities Co. "Like the yen, gold is often bought when investors want to shun risks and it also draws buying when the dollar is weak."
The average retail price of gold stood at 4,396 yen per gram before tax in 2016, sharply higher than 2,287 yen a decade ago, data by Tanaka Kikinzoku Kogyo K.K. showed.
Demand for gold totaled some 4,309 tons in 2016, up roughly 2 percent from a year earlier, the World Gold Council said, as investment surged amid political and economic uncertainty.
The U.S. presidential election and Britain's decision to leave the European Union rattled financial markets last year.
"As uncertainty about the administration led by U.S. President Donald Trump is mounting, it could give support to gold," Kameoka said.
For law enforcement authorities, the task is unlikely to get any easier at a time of increased flows of people and goods. The smuggling of drugs such as stimulants is another major issue.
"It's difficult but we need to get a head start (over smugglers)," the official said.© KYODO