Throngs gather for March for Israel rally at D.C.'s National Mall to ...

Ahead of the rally, at least one pro-Palestinian group, the Washington chapter of the Palestinian Youth Movement, asked its supporters on Instagram “not to engage” with participants at Tuesday’s pro-Israel event.

Speaking via video, Israeli President Isaac Herzog said, "Jews all over the world are assaulted for being Jewish."

"The hatred, the lies, the brutality, the disgraceful outburst of ancient antisemitism are an embarrassment to all civilized people and nations,” Herzog told the crowd. “Jews in America must be safe. Jews all over the world must be safe.”

While Herzog spoke, vendors were selling T-shirts and buttons emblazoned with the names and photos of the Hamas hostages.

Herzog was followed by Senate Majority Leader Charles Schumer, D-N.Y., who took the stage to denounce Hamas and demand the release of the hostages.

"Let them go," Schumer chanted with the crowd.

Schumer was joined onstage by recently elected House Speaker Mike Johnson, R-La., who said now is not the time for a cease-fire.

"The calls for a cease-fire are outrageous," Johnson said. "We stand with you on that."

Schumer and Johnson were followed by “Will & Grace” star Debra Messing, who introduced some of the relatives of the hostages being held by Hamas. She asked people in the crowd to hold up placards with pictures of those kidnapped and appeared to take a swipe at those who see Hamas as Palestinian freedom fighters.

“We are all being tested,” Messing said. “A tsunami of hate has crashed down upon us, and then a deafening silence. We see clearly now. We see naked, virulent Jew hatred being disguised as a noble cause for liberation. And we reject it.”

Netanyahu suggested Sunday there might be a possible deal to release the hostages.

While the event was billed as a "march," the tens of thousands of people organizers had planned for stayed largely within the confines of the National Mall rather than spill out into the streets.

On Sunday, a march against antisemitism through the streets of Paris attracted about 100,000 people and was supported by representatives of the major political parties.

Since the fighting began on Oct. 7, pro-Palestinian organizations have held their own rallies in cities across the U.S. and globally.

Demonstrations have also roiled college campuses as schools struggle to contain escalating rhetoric and threats of violence. They include an Arab Muslim student at Stanford University who was struck in a hit-and-run that authorities are investigating as a hate crime and the arrest last month of a Cornell University junior accused of making online threats to Jewish students.

The Anti-Defamation League said Monday that in the month since the war between Israel and Hamas began, it has documented 832 antisemitic incidents of assault, vandalism and harassment across the U.S. This is a 316% increase from the same period last year.

"As we have seen repeatedly, when conflict arises in the Middle East, particularly when Israel exercises its right to self-defense, antisemitic incidents increase here in the U.S. and around the world," Jonathan Greenblatt, the league's CEO, said in a statement.

The Council on American-Islamic Relations also said it has seen a sharp rise in bias incidents since Oct. 7. Since then, the group said, it has received 1,283 "requests for help and reports of bias," a 216% increase from an average period last year.

Corey Saylor, the council's research and advocacy director, said it was the largest wave of Islamophobic bias the group has documented since the Trump administration implemented an immigration ban.

"Both Islamophobia and anti-Arab racism are out of control in ways we have not seen in almost 10 years," Saylor said in a statement.

Erik Ortiz and Julia Ainsley reported from Washington and Corky Siemaszko from New York City.