Chennai: More than 600 people have been booked for staging a protest against the controversial Citizenship Amendment Act here, police said on Friday.Scores of people across different areas joined the protest against the CAA and the National Register of Citizens at Valluvarkottam on Thursday.The demonstration, organised by a collective of civil society members, Left liberals and volunteers of Jamaat-E-Islami Hind and NGOs saw high pitched slogans against the BJP-led Centre, the RSS, and Hindutva.Cases have been registered against them under Indian Penal Code 143 and Section 41 Class VI.“Yes, cases have been booked under Indian Penal Code Section 143 and (under) Section 41 Class VI,” a senior police officer told PTI.According to Section 143 in the Indian Penal Code whoever is a member of an unlawful assembly, shall be punished with imprisonment of either description for a term which may extend to six months, or with fine, or with both.