Kannan Gopinathan, a former IAS officer from Kerala, was detained by city police soon after he arrived at the airport in Prayagraj, officials said. Mr Gopinathan had arrived in Prayagraj from Delhi on Saturday to address a two-hour symposium organised by the All India People's Forum on the issue of 'Nagrikta Bachao, Samvidhan Bachao, Loktantra Bachao' (save citizenship, save constitution and save democracy).