Coimbatore : Security has been tightened in nearby Pollachi, following large scale protests by students and general public over the sensitive case of sexual harassment and blackmail of a 19-year old girl student by a four-member gang.

Heavy police deployment has been made near colleges and highways in and around Pollachi to prevent any untoward incidents, police said.

A majority of the colleges had been shut by their managements to keep students away from indulging in agitation, they said.

Meanwhile, more visuals are being circulated in the social media involving the gang and students and women, including expelled AIADMK functionary, Nagaraj, suggesting a larger network behind the this sexual abuse, police said.

However, Nagaraj, in a video claimed that the visuals shown in the media were not of his, but that of another accused Sathish.

He said that defamation cases will be filed against those who were circulating such videos.

The case, which was being investigated by Tamil Nadu CB-CID has now been handed over to the CBI following a State government order, police added.