"Every person I listen to - he spoke [Spanish], he spoke it, she's speaking it - it's America!" an angry Schlossberg was heard saying in the almost minute-long clip.
The man threatens to call immigration authorities and also insults the employee on her physical appearance.
"My guess is they're not documented", he says.
Schlossberg is reported to be a commercial lawyer whose office is listed as being across from the Fresh Kitchen where the incident took place.
When the worker tried to answer him they are bilingual and therefore they speak in both languages, the man did not accept it: "This is America", he exclaimed. So my next call is to ICE to have each one of those kicked out of my country.
"Your staff is speaking Spanish to customers when they should be speaking English", Schlossberg tells the restaurant's manager. So apparently immigrants are fine as long as they look white and don't speak Spanish.More news: Nadal cruises into Italian Open third round, Thiem exit
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He then addressed the woman who called him out behind the camera, and made a terribly insensitive comment about her weight. I paid for my welfare, I pay for their ability to live here.
"This is America. Your staff should be speaking English, OK?" he added.
A worker told ABC News after: 'This is New York City, everybody is different here, everybody has different opinions and some people have a hatred mind.
After the video stops rolling, Serrano said the man "threw his sandwich in the area where they have the bananas".
Serrano then gets into a yelling fight with the man, where he tells her to take a break from food and she tells him he should get hit by a vehicle. "At first it was, wow, you're bullying someone that you feel superior to for no reason", the woman said. He got mad, waiting in line for his food.
"They were speaking Spanish because they are friends", the manager said.