Health officials in New York are investigating 20 zip codes where coronavirus hotspots are showing test results above 10% positivity in some cases.
Cuomo said the clusters in Rockland and Orange counties and Brooklyn are the probably the largest clusters in the state since the pandemic.
RELATED: Rockland County battling a spike in COVID cases
The state's positivity rate is 1.1% while the average in the top 20 zip codes is above 5%. In one case, the positivity rate is above 20%.
Cuomo said zip code analysis shows an overlap with large Orthodox Jewish communities.
"That is a fact, so I will be directly meeting with them to talk about it. This is a public health concern for their community; it's also a public health concern for surrounding communities," he said.
Cuomo called on local government to target the clusters.
"A cluster today can be community spread tomorrow," Cuomo said.
Earlier, New York City Mayor Bill de Blasio said the city reported a positivity rate of over 3% for the first time in months.
Cuomo reiterated that he would close NYC schools if they are not safe.
"We will know tomorrow by the data," Cuomo said. "The schools must report to the state the data - they're doing testing. The numbers will tell you the facts, and once you have the facts, you can operate logically. If the schools aren't safe, I am not going to allow them to operate."
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