Nearly 30 percent of 340 cases of child sexual abuse involved abusers who sexually assaulted more than one child, while 40 percent of the abusers were teachers, according to a report released Wednesday.

The report, released by Girls' Protecting - an NGO launched  to help raise Chinese children's awareness of self-protection - at a Beijing symposium, said that of the 340 cases of child sexual abuse revealed by media reports in 2015, 96 involved abusers who had abused at least two children, and 14 of the cases involved abusers who had assaulted at least 10 children.

It is difficult to find out whether children have been sexually assaulted, and they likely would continue to be abused without outside intervention, the report said, adding that abusers may attack more children if they are not stopped.

The report also showed the perpetrators of the abuse in 70 percent of the 340 cases were found to be acquaintances of the victims, including teachers, neighbors and family members. Seven cases involved abusers who had befriended the victims online.

Political advisors have proposed incorporating sex education into the compulsory education curriculum and have called for strengthening the social supervision of minors.

"The government should help families better guard their children. For example, the government could assist social organizations by providing nursing services and participating in temporary or long-term aid," Zhang Xuemei, director of China Child - an NGO dedicated to teenagers' rights - told the Global Times on Wednesday.

Meanwhile, the government should also intervene with families who are found to have a history of sexual abuse through legal procedures, Zhang said.

Zhang added that the country's mandatory reporting system should also be enhanced to encourage guardians to report abusers and to punish those who fail to fulfill their responsibility to report.

Wang Xingjuan, founder of Red Maple Women's Counseling Center, also suggested that harsher punishment be imposed on sexual abusers.