An off-duty New York Police Department officer who is a Muslim was allegedly threatened by a man Saturday after dropping off her son.

WABC reported that Aml Elsokary dropped off her 16-year-old son in a Brooklyn neighborhood. As she returned from parking her car, she saw a man arguing with her son.

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CNN reported that Elsokary, who was not wearing her uniform, intervened and the man allegedly told her, "ISIS (expletive), I will cut your throat. Go back to your country."

According to the NYPD, Elsokary,  an 11-year veteran of the department, was wearing her hijab at the time of the incident.

Christopher Nelson, 36, was arrested and charged with menacing as a hate crime and aggravated harassment within 24 hours of the incident.

Acting Brooklyn District Attorney Eric Gonzalez told CNN Nelson was held on $50,000 bail.

WCBS reported that Elsokary spoke about why she became an officer in the first place.

"I'm born and raised here and I'm here to protect you and I know that my department and my city is here to protect me," she said. "I became a police officer to show the positive side of a New Yorker, Muslim woman that can do the job, that is (unbiased), that I can help everybody no matter what's your religion."

New York City Mayor Bill de Blasio said in a news conference Monday that he was "sick to my stomach" over the incident.

"She serves this city. She is an example of everything we would want from our fellow citizens — a commitment to others, a commitment to service, a willingness to do something greater than herself and what does she get for it? Threats to her life and bigotry, taunts."

"This is her country, she is an American, she is a New Yorker, and this is her home," de Blasio said. "We cannot allow this hatred and bias to spread."