Students, doctors and artists were among the scores of people who gathered at Central Park in Delhi's Connaught Place to protest against the amended citizenship law and the proposed all-India NRC.
Several AIIMS doctors wearing stethoscopes around their neck also assembled at the site where the protesters sang patriotic songs and recited poems.
Organised by a newly-formed group called 'Delhiites For Constitution', several protesters held up placards with catchy slogans like: 'My name is Khan and I am an Indian', 'It is so bad that even engineers are here', 'Make India Democratic Again', and 'Darr ke Aage Peace hai'.
Ajay Verma, psychiatrist at AIIMS, sang songs against the contentious law amid loud cheers and applause by the students.
"It is going to be a long battle. People hurt in protest were not given timely treatment. We have arranged ambulance to provide immediate medical aid to people," Verma said.
Jawaharlal Nehru University professor Jayati Ghosh thanked the youth of the country for starting the movement against the Citizenship (Amendment) Act and the National Register of Citizens (NRC), saying "you gave us hope".
"'Kashmir wali normalcy' is spreading and we want freedom from that normalcy," Ghosh said. "We should not stop now we need to go forward."
Rashmi from Venkateshwara college said there was a need to bring back narrative to real issues like employment and whether ordnance factories would remain as public sector or not.
"These are the questions we should ask, not the CAA being thrown at us," she said.
Sneha Kumari, an IT professional, said people know that CAA was the same tool that demonetisation was.
"Indians have realised that, they cannot fool us anymore," Kumari said.
Satish Raghav, a Delhi University student, said this country was not of the 303 MPs sitting in Parliament, but of the 1.3 billion Indians.