An Egyptian teenager has been stabbed to death while trying to defend a woman from sexual harassment, according to an activist group.

Ahmed Fayed, 17, was reportedly stabbed in the chest after stepping up to save a woman from a group of men sexually harassing her in Ras al-Bar City, in the governorate of Damietta, according to the group I Saw Harassment.

The group, which set up an initiative aimed at providing women with safe celebrations during the Islamic feast of Eid al-Adha, said the body of the teenager was taken to a local hospital where an autopsy is to be performed. Police are searching for the assailants.

According to I Saw Harassment, 25 cases of sexual violence were reported in Cairo during the second day of Eid, which took place over the weekend. The Muslim festivities have become associated with sexual harassment in Egypt's streets.

A 2013 UN study found that 99.3% of Egyptian women have suffered some form of sexual harassment, up to and including being sexually assaulted.

Egyptian authorities recently amended the Penal Code to criminalise sexual harassment.

The news came after prosecutors in Minya ordered a probe into nine police officers accused of the sexual harassment of a woman.