A post on the restaurant's Facebook page Sunday night said Aldo Bazzarelli was intubated and "fighting for his life" while Mr. John -- his father-in-law -- was on oxygen but stable.
The pair started the restaurant together in 1971 making pizza at its former Moonachie Road location, while Aldo's wife, Costanza, watched their newborn baby with Angelina, Aldo's mother-in-law.
The restaurant, which later moved across the street to its current location at 117 Moonachie Road, closed to the public on March 23. It was expected to open Monday.
Condolences from hundreds of customers came pouring in, most of who remembered Aldo as a "kind and wonderful man."
"I was new to this area and your father welcomed us with open arms," one said. "Always a pleasure to see him for my to go orders - he will be greatly missed."
"Our entire family is heartbroken," another said.
"We have celebrated so many important events at Bazzarelli's, communions, confirmations, birthdays, and Aldo also made us feel like family.
"He remembered my children's names and [never] let us leave without a hug. Sending you our love and prayers to your entire family and staff."
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