TOKYO, Japan — Japanese cosmetics and retail stocks are taking a hit after Chinese social media reports spurred speculation the country is increasing scrutiny over its citizens bringing in goods from overseas.

Cosmestics giant Shiseido Co. was the single-largest contributor to the benchmark Topix's drop. The Topix Chemicals Index, which includes a host of cosmetics firms, weighed most on the market among 33 industry groups. Ryohin Keikaku Co., the operator of popular apparel chain Mujirushi Ryohin, was the biggest contributor to the retail sector's losses in early afternoon trading in Tokyo.

Chinese citizens returning from overseas trips should declare to customs if the value of the goods exceeds the tax exemption amount, China National Radio reported, citing a Shanghai customs employee. There’s widespread speculation on Chinese social media that Pudong Airport has recently stepped up checks on those bringing in goods purchased overseas, the report said.

Drug chain operator Welcia Holdings Co. and discount store operator Don Quijote Holdings Co. were among the companies weighing most the retail sector’s declines. The Topix Retail Trade Index was down 0.9 percent, underperforming the broader market. Among cosmetics makers, Kao Corp. slid more than 3 percent while Kose Corp. dropped 6.4 percent.

Japan isn’t the only country being whipsawed by concern over a potential decrease in demand from Chinese tourists. Retail and tourism-related companies in the region are often victim to the rise and fall of demand from China, Asia’s largest economy.

South Korean cosmetics makers declined Thursday as investors reacted to a report published Tuesday that visitors from China fell at the start of this month, coinciding with the week-long National Day holidays. The Kospi index resumed trading following a holiday on Wednesday. AmorePacific Corp. fell as much as 13 percent to lowest since January 2015. Cosmax Inc. slid 9.6 percent, while LG Household & Health Care Ltd. lost 6.6 percent.

There hasn’t been any official policy changes recently, the customs agent said in response to questions on the “daigou” business, or overseas agents buying for Chinese customers, CNR added.

“Data from Japan, Hong Kong, Macau, and Korea points to China passenger traffic growth moderating quite significantly in recent months,” Jefferies analysts led by Stephanie Wissink wrote in a note. “Beauty is the number one purchased category by outbound Chinese travelers worldwide, as more than 50% make beauty purchases while outside of China.”

By Min Jeong Lee and Amanda Wang, with assistance from Heejin Kim, Dominic Lau and Shintaro Inkyo; editors: Divya Balji, Teo Chian Wei and Naoto Hosoda.