Authorities are on high alert due to what's expected to be an unprecedented rally in support of Israel on Tuesday in Washington, D.C.

Thousands of people are gathering on the National Mall to show solidarity with Israel and demand the release of hostages held by Hamas.

The rally is organized by the Jewish Federations of North America.

On Tuesday, New Yorkers joined Americans from many states in attending the "March for Israel" in the nation's capital. Participants said the march is aimed at freeing the hostages and demonstrating against antisemitism.

At least 50 people with the the Jewish Federation of CNY are attending.

“Every congregation is represented, every organization," said Marci Erlebacher, executive director Jewish Community Center of Syracuse. "It is a huge cross section of our community that is going to be on this bus.”

Rochester sent five buses before 4 a.m. Tuesday. Albany hosted a caravan of buses last night, and held a rally near the state Capitol on Monday evening. 

Organizers said at least 100,000 people are expected to march at the D.C. rally, and are seeing a wide range of support. The Buffalo Jewish Federation sent two full buses.

“So there's really three objectives," explained Rob Goldberg, chief executive officer of the Buffalo Jewish Federation. "The first is to express our gratitude to the U.S. government for its solidarity and support of Israel on many levels. The second thing is to call attention to the fact that there's still 243 hostages still in Gaza, that we are demanding their safe return. And the thing is to show the people of Israel that we are with them, shoulder to shoulder.”

The rally at the National Mall is expected to be one of the largest pro-Israel rallies held in the U.S.

Follow Spectrum News 1 for updates.