Several hundred activists and supporters of an American Jewish organization supporting the Palestinian cause carried out a raid on Thursday at Trump Tower, the New York home of the US president, denouncing his crackdown on freedom of expression.

Dressed in red T-shirts with white writing, in reference to the "Make America Great Again" movement popularized by Donald Trump, these people, who responded to the call of the Jewish Voice for Peace organization, took over the ultra-secure Manhattan skyscraper late in the morning.

"Fight the Nazis, not the students," they chanted in chorus, before some were forcibly removed from the hall, which was covered in gilt and pink marble, AFP journalists observed.

According to the New York police, 98 people were arrested. By early afternoon, calm had returned to Trump Tower.

The protesters were referring to the arrest last weekend of a leading figure in the pro-Palestinian protests at New York's Columbia University, which sent shockwaves across the country and sparked outrage among free speech advocates.

"Free Mahmoud, Free Palestine," read one banner, again in connection with the deportation detention of Mahmoud Khalil, despite holding a permanent resident green card. The young man was acting as a spokesperson for a Columbia student movement against Israel's war in Gaza.

- "Fascists" -

Her arrest reveals "that we are on the brink of a total takeover by an authoritarian regime," said Jane Hirschmann, who describes herself as a descendant of Holocaust survivors.

"As Jews of conscience, we know our history and where it leads. This is what fascists do," she added.

"I am here to (...) demand that our Jewishness not be used as a weapon to violate the rights of American citizens and end democracy," declared James Schamus, a "Jewish professor" at Columbia.

For him, the fight against anti-Semitism displayed by Donald Trump is a "smokescreen".

The idea that "we could be abducted from our streets and expelled from the country if we express political opinions about this conflict abroad should send shivers of terror down our spines," he insisted.

Donald Trump has been targeting universities for several days, promising, in the name of combating anti-Semitism, retaliatory measures against institutions that are not fighting the protests shaking universities against the war in Gaza effectively enough for his liking. His administration has already cut $400 million in funding from Columbia.

He also threatened to deport foreign nationals who participated in the protests. He promised that the proceedings against Mahmoud Khalil would be followed by "many others."