The drop in Japanese tourists last month is adding concerns to the faltering local tourism industry already reeling from a dearth of Chinese visitors amid diplomatic jitters with neighboring country, industry and government sources said Thursday.

Some 165,700 visitors from Japan came to South Korea in April, down 5.4 percent from a year earlier, according to the latest data release by the Korea Tourism Organization. 

The tally on Japanese travelers had been on an upturn since February last year, when it rebounded for the first time in more than three years.

Growing security concerns on the Korean Peninsula in the wake of the latest series of missile tests by North Korea over the past two months has probably caused Japanese visitors to shun Seoul, the state tourism agency said.

The bulk of cancellations came apparently from schools that had planned on coming on field trips here, according to the KTO.

The decline from Japan deals a blow to the local tourism sector that has been hit hard after China banned travel agencies from selling South Korea-bound trips from mid-March. Seoul's deployment of a US anti-missile system, or THAAD, has angered Beijing who sees it as a threat to its own security.

With the number of Chinese visitors more than halved compared to a year ago, boosting Japanese demand has been one of key plans for the government to revitalize the tourism sector.

The government has set a string of initiatives aimed at fueling tourism, with a focus on diversifying tourist portfolios to other Asian countries instead of relying too heavily on China.

In contrast, the number of outbound visitors to Japan jumped 56.8 percent on-year to 554,600 in April from the previous year, according to government data. (Yonhap)