The U.S. State Department on Friday credited Japan with making "modestly increased" efforts against human trafficking in 2015, including the identification of some labor-trafficking victims for the first time in two decades.

However, serious shortcomings mean Japan does not meet minimum standards for eliminating the problem, the department said in its annual Trafficking in Persons report.

The report cited failure to prevent the entrapment and trafficking of underage girls in the so-called JK sex industry and said conditions of forced labor persist within the government's Technical Intern Training Program (TITP), which has "effectively become a guest worker program."