A recent surge in the number of Vietnamese students and technical interns going to Japan has resulted in the changing expat demographics, according to public broadcaster NHK.

The number of Vietnamese residents living in Japan reached 448,053 last year, up 10 percent from the previous year and an increase of more than 10 times over the past 10 years, according to data from the Japan's Immigration Services Agency.

In recent years, the growing presence of Japanese companies in Vietnam has sparked greater increased interest among younger Vietnamese to study and/or undertake technical training programs in Japan in the hope of landing a well-paid job.

China topped the expat list with 778,112 and South Korea was third with 426,908 people.

There were about 2.89 million foreign nationals in Japan at the end of last year, down by about 46,000 over the previous year. Vietnamese expats accounted for more than 15 percent of total foreign nationals in the country.

Meanwhile, 15,875 foreign nationals were ordered to leave Japan for overstaying their visas and other reasons last year. Nearly 70 percent of them, or about 11,000 people, were working illegally, mainly in the agriculture and construction sectors, the NHK reported.

Starting this month, Vietnam Airlines and Vietjet have been allowed to resume commercial flights connecting Hanoi and HCMC to Japan's Tokyo.