Forty-six victims of human trafficking were rescued from forced prostitution or forced labor in Japan in 2017, down slightly from the 50 assisted during the previous year, a government report showed Friday.

Of those rescued, Japanese nationals made up the largest share — at 28, a record high — followed by eight Thai nationals and seven Filipinos. There was one victim from each of Vietnam, Brazil and Mongolia.

The victims were all female except for one Japanese boy. The Japanese boy, five Japanese girls and one Filipino girl were aged 17 or younger, according to the report.

Many of the Japanese victims were sexually exploited. Foreign nationals were also largely forced to work as prostitutes or hostesses.

"Human trafficking is a serious human rights violation and a grave international problem," said Chief Cabinet Secretary Yoshihide Suga, who chaired a government meeting to discuss measures to prevent human trafficking the same day the report was released.

The report is based on an action plan compiled by the government in December 2014 that calls for the reinforcement of immigration controls and improved support for trafficking victims.