Japan remained in a group of countries the United States judges to fully meet minimum standards for the elimination of human trafficking, according to a State Department report released Thursday.

The department placed Japan in Tier 1, the highest classification on the four-tier list, for the second straight year because “authorities continued to demonstrate serious and sustained efforts during the reporting period.”

The ranking categories are Tier 1, Tier 2, Tier 2 Watch List and Tier 3.

The department cited Japan’s efforts such as increasing labor inspections of the nation’s Technical Intern Training Program and convicting and incarcerating more traffickers than in the previous year.

Last year, Japan was upgraded from Tier 2, partly due to the launch of an interagency task force to combat enjo kōsai, or compensated dating, and the “JK business,” which offers dating services by joshi kōsei, or female high school students, for adult men.

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According to the 2019 Trafficking in Persons Report, Japanese authorities continued to take law enforcement action against child sex trafficking in JK businesses, with seven prefectures passing ordinances banning such businesses.

The ordinances prohibit girls younger than 18 from working in compensated dating services and require JK business owners to register their employee rosters with local public safety commissions, it said.

The report, however, said Japan can do more toward the elimination of trafficking. It accused the government of not fully enforcing technical intern reforms aimed at blocking foreign-based recruitment agencies from charging excessive fees, and recommended harsher sentencing practices.

“Authorities continued to prosecute traffickers under laws carrying lesser sentences, which courts often suspended in lieu of incarceration, and they continued to suspend the majority of convicted traffickers’ prison sentences. Some traffickers received only fines,” it read.

In the report, countries with poor human rights records such as China, North Korea, Russia, Iran, Syria, Myanmar and Venezuela remained on Tier 3, the lowest level.

Some of these countries allow human traffickers to run rampant, and others are human traffickers themselves, U.S. Secretary of State Mike Pompeo said in launching the 2019 report.

“In North Korea, the government subjects its own citizens to forced labor both at home and abroad and then uses proceeds to fund nefarious activities,” Pompeo said.

“In China, authorities have detained more than a million members of ethnically Muslim minority groups in internment camps,” he said. “Many are forced to produce garments, carpets, cleaning supplies and other goods for domestic sale.”