WASHINGTON — Hundreds of thousands of people are expected to fill the nation’s capital for the inauguration of Donald Trump today, and while the majority of those will be there to celebrate, some protesters say they plan to disrupt the day.

Late Thursday evening, protesters and supporters of Trump clashed outside an event at the National Press Club. Police used chemical spray in an effort to control the unruly crowd.

In New York, actors Robert De Niro, Sally Field and Mark Ruffalo joined hundreds of other people outside a Donald Trump building Thursday for a pre-inauguration demonstration.

A coalition calling itself DisruptJ20, after the date of the inauguration, said it will attempt to block or cause delays at security checkpoints going in to the inauguration ceremony.

One DisruptJ20 event is a march that will begin at Columbus Circle, outside Union Station at noon, the same time Trump is being sworn in as the nation’s 45th president, and traveling about 1.5 miles to McPherson Square, a park about three blocks from the White House.

Along the official parade route, the anti-war group the ANSWER Coalition will demonstrate at two locations.

And a Women’s March on Washington is planned for Saturday.

Christopher Geldart, the District of Columbia’s homeland security director, has said 1,800 buses have registered to park in the city Saturday, which would mean nearly 100,000 people coming in by bus.