The constitution of 1972, offered by Father of the Nation Bangabandhu Sheikh Mujibur Rahman, must be brought back for a secular state, said social scientist Dr Anupam Sen.
He made the remarks at a rally in Chattogram on Thursday.
The rally was organised by the Chattogram divisional committee of the International Society for Krishna Consciousness (ISCON).
"Everyone must come together to stop those who instigate communal disharmony. The recurrence of such incidents will be prevented by ensuring maximum punishment for those involved in the attack, the attackers and the instigators," he said.
Among others, the former mayor of the port city and Chattogram Awami League General Secretary AJM Nasir Uddin, Chattogram BNP Convener Shahadat Hossain, ISCON Chattogram division chief Chinmoy Krishna Das were present at the rally.
"There is no place for communalism in a secular country. Like you, I am saddened by the communal attacks. Prime Minister Sheikh Hasina is very sincere towards the minority community. Where communal incidents have taken place, immediate action has been taken on the instructions of the prime minister," AJM Nasir Uddin said.
"BNP believes in secular consciousness. Those who are actually involved in the attack should be brought under the law. We should ensure that no innocent person is arrested or that the incident is diverted. Let's all work together to build resistance against communalism," Shahadat Hossain said.