According to police, SP corporator Varun Singh allegedly shared the said photos on his account on a social networking site. The post drew a large number of comments, police said.
The complaint in the matter was filed by a local following which an FIR was lodged against Singh last Wednesday at Lanka police station.
Now, Varanasi Crime Branch has opened a probe into the matter, they added.
Meanwhile, Singh has told police that his account on the website was hacked and somebody else had posted the pictures.