The incident took place on Tuesday morning in the Alfortville commune in the Paris suburbs, some 4km from the French capital.
Crowds of undocumented migrants from several communes, including the neighboring Vitry, Montreuil, and Courbevoie, headed to the town hall, Le Parisien reported.
The protesters apparently wanted to speak with local authorities and discuss the rights of foreigners. According to local newspaper 94.Cityoens, at least 200 people turned out for the protest.
Town hall staff told Le Parisien that they hadn’t noticed the demonstrators’ arrival until it was “too late.”
The protesters blocked access to the building by forming a human chain. Police officers who arrived at the scene deployed tear gas against the migrants.
Alfortville : une manifestation de travailleurs sans-papiers dégénère https://t.co/5SrhRRtTa2— Le Parisien | 94 (@LeParisien_94) April 18, 2017
The video released by the newspaper shows protesters facing off with police at the entrance to the town hall. Some of the demonstrators are then seen lying on the ground, apparently injured.
At least 14 illegal immigrants were treated by medical staff for respiratory problems from the tear gas, local media reported. One person also told Le Parisien that he was “beaten by a baton,” although it’s unclear if he was a migrant or a passerby.