A fence was installed before Harris’ speech at the Ellipse in Washington.

A new permit issued to the Harris campaign says up to 40,000 people are expected to attend.

The event, for which doors open at 3 p.m. ET, was announced to Harris supporters through push alerts, emails and online advertisements.

The Secret Service said in a statement to ABC News that it was “working closely with our federal and local partners to ensure the safety and security of Vice President Harris and all participants in Tuesday’s campaign event at the White House Ellipse.

Several protest groups have announced plans to protest Harris’ speech, including a large group of anti-war and pro-Palestinian demonstrators from several well-known Washington-based groups.