The Delhi Police, on Monday, detained 178 Congress party workers and leaders for violating prohibitory orders imposed under section 144 while holding a 'Satyagraha' at Jantar Mantar against the summoning of Rahul Gandhi by the Enforcement Directorate (ED), officials said. According to the police, a request was received from the secretary of the All India Congress Committee (AICC), seeking permission to hold a Satyagraha on Monday here at the Jantar Mantar.