The city's health department was notified of the gnats at the Hudson Mall Shopping Center on Route 440 on Dec. 30, 2019, several media outlets report.
Vendors say the tiny flies have been keeping business at bay.
Several bothered customers took to Yelp to complain.
"As soon as me and my friends walked in, I had a fly, flying around me,” one Yelper said. "And they’re not big ones, they’re little fruit flies, but still nasty.”
The mall's owner, Urban Edge Properties, said they jumped to remedy situation -- immediately fixing the pipe and installing fly traps, deemed safe and effective by mall management and city health officials.
The situation will continue to be monitored by health officials daily, a Jersey City spokeswoman said.
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