The school announced the suspensions in a tweet over the weekend.
In subsequent messages, the school said it received reports and videos of large crowds of young people gathering in Washington Square Park Saturday night, with some people not wearing masks or distancing.
NYU leadership is investigating and promises "swift action" if any students took part.
MORE: NYU plans for in-person classes in the fall
The school released a statement on Monday saying:
"With regard to the recent activities in Washington Square Park, there appears to have been a wide cross section of people of various ages involved, but we've made it emphatically and repeatedly clear to our students that the safety and health rules we've put in place this year apply at all times - whether they're on campus or off campus in public parks, such as Washington Square Park. Our Office of Student Conduct has been aggressively enforcing these rules and will continue to do so (we've issued more than 20 suspensions to date). If we confirm that any of our students were involved in these gatherings and acting in violation of our health and safety protocols, we will take swift action. We also sent another message last night to all students reinforcing the importance of keeping each other safe.
"Testing at NYU has been going on since mid-August. The second phase of testing - ongoing testing- begins this week. Phase 1 - arrival testing - began in mid-August for students, and involved more than 17,000 tests, with 17 positives as of Aug 28. Those with positive tests were isolated and are being overseen by NYU's COVID-19 Prevention & Response Team. There will be more information on testing posted to our NYU's coronavirus hub website next week."
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Earlier this week, NYU's Senior Vice President for Student Affairs Marc Wais sent a message to students reminding them of the school's policies and urging them to stay away from gatherings where there are no masks or social distancing.
The memo says the university will investigate every report it receives of an alleged violation of its guidelines.
Students found to have participated in gatherings that do not abide by the rules risk being suspended for one semester and anyone found to have hosted a party that fails to take safety precautions will likely be suspended for the full academic year.
Samuel Wu is a freshman from LA, a hot spot, who took part in the mandatory 14-day quarantine when he first got to campus. He said the video from Washington Square Park is upsetting.
"We worked so hard to get here and it's like why are you putting us all at stake," Wu said.
While other students seem to agree, some said they see why the park gatherings might have happened.
"There's nowhere to make friends and go see people, so people come to an outdoor place like this park, it's tough to say," NYU student Taylor Robbin said.
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