Mayor de Blasio joined protestors in Lower Manhattan to speak out against President Trump's executive order. They say they expect this fight to continue. NY1's Lori Chung filed the following report.

Thousands marched in Lower Manhattan on Sunday to denounce President Trump's executive order that bans entry to the U.S. by people from seven Muslim-majority countries.

"We have seen an order that makes no sense on its face. It is filled with contradictions, has caused confusion. But under all that we see the beginning of the degradation of our civil liberties and our constitutional rights," Mayor BIll de Blasio said at a rally Sunday in Battery Park. "We are not fooled. We know where this leads and how dangerous it is."

Protesters also marched to Foley Square, chanting, "No ban, no wall."

Hundreds of police officers were in Foley Square to make sure protesters stuck to what appeared to be a pre-approved route.

Some streets were closed to allow demonstrations in the area.

A variety of activists and organizations marched from the Manhattan park to 26 Federal Plaza, the site of many federal government agencies.

Participants included members of the National Immigration Law Center and Service Employees Union 32BJ, who said they want to show solidarity with the refugees and immigrants being detained at airports around the country.

The protesters were scattered around the tip of Battery Park for a few hours before they went on the move.

De Blasio, Senate Minority Leader Chuck Schumer, and other elected officials spoke prior to the march, saying the travel ban is unconstitutional and must be rescinded immediately.

Trump's order, which he signed Friday, bans entry to the United States by residents of seven Muslim-majority countries — Iraq, Syria, Iran, Libya, Somalia, Sudan, and Yemen —for the next 90 days.

The Queens native's executive order also bans U.S. entry of those fleeing war-torn Syria indefinitely, and bans the admission of all refugees for the next four months.

The executive director of the Port Authority, Pat Foye, said the federal government has put a chokehold on providing information about the exact number of travelers being detained.

A federal judge in Brooklyn had issued a stay on the executive order Saturday, preventing deportations of those people if they have valid visas.

The stay, which covers the entire country, awaits further legal review.

That judge's ruling, however, does not prevent people from still being detained.

Trump said Christian refugees will be given priority over Muslims.

The White House said Sunday that green card holders will not be affected moving forward.