On Friday, protesters were evacuated by the police a couple of hours after they surged the Panthéon. Videos on Twitter showed protesters sitting in the streets around the monument’s plaza, an area popular with tourists and students on the city’s Left Bank. Some chanted: “What do we want? Documents!” Others were seen being arrested by the Paris police.

The far-right leader Marine Le Pen called the occupation unacceptable. “In France, the only future for any illegal immigrant should be getting kicked out, because that’s the law,” she wrote on Twitter.

A lawmaker from the far-left party France Unbowed, Eric Coquerel, and a Green Party senator, Esther Benbassa, supported the movement. “We can’t keep having such a restrictive immigration policy, with a reception that doesn’t stand up to the humanitarian principles that France accustomed us to,” Ms. Benbassa said in front of the monument.

Since he was elected in 2017, France’s president, Emmanuel Macron, has vowed to tackle illegal immigration and to contain an ever increasing number of asylum requests — more than 122,000 in 2018, up from 100,000 in 2017 and from 85,000 in 2016. With a tough approach to migrants, he has also tried to head off any progress of the far-right and anti-immigration National Rally, which won the most seats of any French party in the European elections in May.

From an asylum outpost in Niger, a hub for African migrants, France has aimed to discourage would-be migrants tempted to try a perilous journey toward Europe and France. To those coming from West African countries deemed safe by France — Benin, Senegal, Ghana — chances to be granted asylum are slim. Many others can linger for months before receiving an answer.

But the most stringent measure has been an asylum and immigration law passed in 2018 that human rights organizations and lawmakers in Mr. Macron’s own party have denounced as too harsh on migrants.

Migrants who enter France illegally now have 90 days to apply for asylum under this law, down from the 120 they had before the new law. Rejected applicants now have 15 days to appeal instead of a month, while those deemed ineligible can be held in “administrative detention” for 90 days instead of 45, before being expelled.

Interior Minister Christophe Castaner said in November that the number of deportations in 2018 increased by 20 percent from 2017.