Riot police took action after a group of protesters pelted officers with bottles and candles from one of the tributes to the victims of the November 13 attacks on the French capital. Around 100 people were arrested.
Organisers said around 10,000 activists had linked hands in a peaceful protest near the site of the deadliest attack, pleading for leaders to curb global warming. Police said half that number took part.
Stretching for two kilometres long a wind-blown Boulevard Voltaire in eastern Paris, it was the first organised demonstration since the attacks claimed by the Islamic State in which 130 people died and hundreds were injured.
Out of respect for the dead, the protesters left a 100-metre gap in front of the mass of flowers and candles laid outside the Bataclan.
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"Hear our voices! We are here!" cried the demonstrators ahead of the 195-nation UN summit being held just outside Paris, which aims to strike the first truly global accord to limit greenhouse emissions and avert a global climate disaster.
In emotional scenes and guarded by heavily armed police, Chilean President Michelle Bachelet visited the Bataclan memorial, met with a relative of one of the three Chilean victims and laid a large floral wreath.
But around two hours after the human chain dispersed, anti-capitalist protesters who had gathered in the nearby Place de la Republique square that has become a rallying point for mourners after the attacks began to clash with police, AFP reporters said.
As objects were thrown, police in riot gear formed lines to push back the protesters and the air was filled with teargas.
French President Francois Hollande described the violence as "scandalous" and blamed it on "disruptive elements".