Fifty people were rescued from human traffickers in Japan in 2016, with Japanese nationals making up half of the victims, a government report showed Tuesday.

Of the 50, 13 were aged 17 or younger, according to the annual report approved by the government.

"We need to discover and protect victims who have difficulties seeking help," Chief Cabinet Secretary Yoshihide Suga told a government meeting to discuss measures to prevent human trafficking.

According to the report, 48 of the victims were female, including 25 Japanese nationals whose number nearly doubled from the previous year. Nine were Thai nationals and eight were Filipinos.

Many of the Japanese victims were forced into prostitution through online dating sites. Foreign nationals were largely forced to work as hostesses or prostitutes.

The annual report is aimed at helping prevent human trafficking operations by raising public awareness.

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