Kolkata, Feb 3 (IANS): Bengali filmmaker Anindya Chatterjee, who was within a "stone's throw" of Paris-based satirical weekly Charlie Hebdo's office when it was attacked Jan 7, has documented the massive protest march following the incident.

Seventeen people were killed in Paris in attacks at the magazine's office, on a police officer, and at a kosher supermarket.

The attackers said the act was in retaliation to Charlie Hebdo's cartoon depicting the Prophet Mohammed.

Chatterjee's documentary "Extremism Denied" (working title) was filmed Jan 11 when relatives of the victims of the attacks led a rally from Place de la Republique to Place de la Nation.

"For the march, all public transport was declared free to enable people to participate. Some carried posters and placards that said 'Je suis Charlie' (I am Charlie). Beatles' songs were played at some junctures."

"The mood was very different on that day when I asked people about their views on the attacks," recalled Chatterjee, who was in Paris to shoot another film.

More than 40 world leaders, including German Chancellor Angela Merkel, Israeli Prime Minister Benjamin Netanyahu and British Prime Minister David Cameron, joined the beginning of the unity march with their arms interlinked.

It is estimated that up to 1.6 million walked to demonstrate unity.

However, when the independent filmmaker went out a few days later, it seemed to him that things had calmed down and people were getting on with their lives.

"The mood had changed then and I have captured that too. My film is not just a glimpse of the French view, but also provides a global perspective. In addition, it subtly questions the idea of complete freedom of speech," he told IANS.

Chatterjee, whose first Bengali film "Jhumura" is awaiting release, is currently in the process of editing the documentary.