A couple of affluent Bergen County communities are in the spotlight after reports of crowded house parties.

An Alpine residence where a recent pool party attracted throngs of paying party-goers, is under investigation by the Bergen County Prosecutor's Office.

The neighboring borough of Cresskill has been dealing with reports of new coronavirus cases after some house parties there, according to the Office of Emergency Management, which did not return requests for more information.

Shortly after one Cresskill High School graduate tested positive, the number of new cases was up to 20 by Tuesday, Daily Voice Bergen County reported.

The Saturday event in Alpine was at a Hemlock Drive property owned by Hudson County attorney Joseph LaBarbiera, as reported by NorthJersey.com, which cited Alpine's mayor and property records.

Gov. Phil Murphy said Monday that he had not liked what he'd heard so far about the situation in a community that consistently has been ranked as New Jersey's most expensive ZIP code.

"If in fact people were bused in and it was a promoted party. That’s not going to end well either for the sponsors of the party ... or, I hope I’m wrong about this, the health of the people who were there," Murphy said.

NBC New York reported the same property held another large party last month, billed as "Bikinipalooza" on Instagram.

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