WATCH | Green Party presidential candidate Jill Stein explains why she's protesting outside the Hofstra University debate.
Civil disobedience action
Twenty-four protesters were arrested at Hofstra University ahead of the first presidential debate on Monday, the Nassau County police department confirmed to Circa.
All of the arrests were on disorderly conduct charges, Nassau County Police Department spokeswoman Jean DeLuca said. She added that there were no "major incidents" but offered no other details.
Several of the arrests happened at a planned peaceful civil disobedience action orchestrated by Green Party candidate Jill Stein.
During that action, about 50 Stein supporters tried to walk through an area that had been closed off by police.
When police lined up to block the protesters, they sat down on a closed-off street.
WATCH | Here is some video of that action, and the subsequent arrests.
Stein escorted off campus
Stein did not participate in the sit-in protest. After giving brief remarks outside the University to her supporters, she hopped in a black SUV and left.
Stein's spokesperson did not respond to Circa's request for comment.
Earlier in the day on Monday, Stein had been escorted off Hofstra's campus by police while she was trying to do interviews with various media outlets. Police said Stein did not have the proper credentials to be within the blocked off area on campus. Stein was not arrested.
Stein tweeted about her civil disobedience action before it happened Monday.
Stein supporters told Circa they were protesting due to Stein's exclusion from the debate. Stein had not reached the 15 percent national support required to participate.
"We believe America has a right to hear all of the options that they have to vote for this year, not just the two corporate parties," said Diane Moxley, a Stein supporter.
Initially, the action was supposed to be much bigger. But logistical problems with police blockades on campus prevented two large groups of protesters from combining.
Moxley complained about said logistical problems on Twitter.
WATCH | Jill Stein speaks out on climate change and the economy outside Hofstra University on Monday.
Stein supporters, however, were not the only people demonstrating outside Monday's historic presidential debate.
WATCH | Donald Trump supporters were also among the thousands of protesters that showed up.
One third of police force on duty
The Nassau County Police Department previously confirmed to Circa that 1,000 officers -- or about one-third of the entire force -- would be deployed for the debate.
Police helicopters and a high-tech security balloon were also deployed, CBS New York reported.
WATCH | Jill Stein breaks down "Blacks Lives Matter" outside the Hofstra debate on Monday.
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