Singh condemned the act and said he will initiate an inquiry into the matter.
"I will look into the matter. Whether it is picture of Gandhiji or Mahamanaji this kind of act showing disrespect to such legends is condemnable," Singh told reporters here in reply to a question.
He said that he would ask the BHU Press Publication and Publicity cell in-charge to inquire the matter and also send a written statement to media stating that this kind of act must not get repeated by anyone.
It is alleged that one of the posters at an AAP rally showed BHU founder Mahamana Pandit Madan Mohan Malaviya's picture with a broom (AAP's symbol) above its head.