What is the controversy over claim of a 'temple in Qutub Minar' all about?

National Monuments Authority (NMA) Chairman and BJP leader Tarun Vijay on Thursday said the Ganesha idols placed "disrespectfully" in the Qutub Minar complex should either be removed or installed "respectfully". The former MP said he had raised the issue with the Archaeological Survey of India (ASI) more than a year ago but is yet to receive a response to his letter.