HEMPSTEAD, N.Y. — Demonstrators are expected at Hofstra University for Monday night’s showdown between Donald Trump and Hillary Clinton, but police are keeping them at a distance from the debate hall.

Police are setting up a designated protest area that is across a six-lane roadway from the actual presidential debate site. They say the goal will be to keep opposing groups from tangling with each other.

“We’ll segregate the groups in order not to pour gasoline on a fire,” said Thomas Krumpter, the acting Nassau County police commissioner. He said police will not tolerate “any violations of law, but we will do everything we can to protect people’s rights for free speech.”

Police and state court officials said contingency plans are in place in the event of mass arrests. They are preparing for up to 10,000 demonstrators, though its unknown how many might actually attend.

Susan Gottehrer, director of the Nassau County chapter of the New York Civil Liberties Union, said her organization will have about 10 people monitoring the activities of police and demonstrators.

Hofstra University, 25 miles east of New York City, was tapped this summer to pinch-hit as host for the first presidential debate after Ohio’s Wright State University dropped out.

Police officials say the experience of hosting presidential debates at Hofstra in 2008 and 2012 is helping them prepare for Monday night’s debate.

Krumpter said 1,000 officers will be on hand for the event, in addition to the Secret Service and state police, up from 600 officers in 2008 and 700 in 2012. The estimated cost of policing the event for the Nassau department is nearly $2 million.

Michael Balboni, a former adviser on public safety to two New York governors, said the basketball arena where the candidates will debate is ideally insulated within the campus, and hundreds of yards from dormitories and classrooms, allowing planners to have several layers of security zones.