Authorities said the aim of the operation was to "guarantee the safety and health" of the 2,000 migrants but an NGO deplored that there were few social workers or mediators to assist.
French police officers began dismantling an illegal migrant camp near Paris on Tuesday morning where more than 2,000 people lived in difficult conditions.
The operation to clear the camp located under a motorway slip road in Saint Denis, northeast of Paris, and resettle its residents started at around 07:00 CET. Seventy buses were to take the migrants to reception centres and sports halls in the Ile-de-France region.
Law enforcement authorities said on Twitter that the operation would "guarantee the safety and health of all, especially against COVID-19."
Paris Police chief Didier Lallement added that "these camps are unacceptable".
"This operation aims to ensure that people in a regular situation are sheltered and those in an irregular situation are not intended to remain on the territory," he said.
The camp housed more than 2,000 people, according to the France terre d'asile ("France country of asylum") NGO. The majority of them were men, primarily from Afghanistan, Sudan, Ethiopia and Somalia.
The NGO described the operation on Twitter as "vital" and "long-awaited." Its director, Pierre Henry added: "I welcome the sheltering of some 2,000 people, temporary residents of a place of indignity near the Stade de France."
"In five years, this must be the 301st operation of this kind. Reception in safety and dignity is possible," he added.
However, the Solidarité Migrants Wilson NGO deplored that "as usual, there are more police officers than social workers."
"A lot of questions from migrants (where are the buses taking us...) go unanswered.
"No mediator, according to WATIZAT [another NGO]. It's historic, the fist evacuation organised only by the police without the help of the town hall or administrative aid institutions," it added.