A?video clip showing a topless female student having her breasts stroked by a group of teenage schoolboys has caused outrage and sparked an investigation by education and public security authorities.

The three-minute video has been circulated widely online and was reportedly shot in the classroom of a vocational school in Cixi City, Zhejiang Province.

An official at the Cixi Education Department told the Oriental Morning Post on Wednesday it had launched an investigation.

The head of Cixi police's political department said the Internet monitoring department of the Cixi public security bureau had intervened because the case might be linked to criminal charges of spreading pornographic material online.

In the video, the female student told one of the boys she was 19. Most of the conversation was in a local dialect and hard to understand.

The girl asked a boy filming her with a mobile phone to stop but was told: "It's only for us classmates and won't be shown to anybody else."

(Shanghai Daily July 3, 2009)