Vice President Kamala Harris will deliver an address to voters Tuesday evening from the Ellipse in Washington, prompting road closures and heightened security in the District of Columbia.

According to the event’s permit, there are as many as 20,000 people anticipated to attend. Metropolitan Police Chief Pamela Smith has estimated that there could be up to 50,000 attendees. Overflow crowds will be directed to the northeast portion of the National Mall near the Washington Monument.