New York City parents were shocked and infuriated to discover that their nanny brought their 1-year-old baby on her trek from from the Upper West Side to Mahwah where she set her ex-boyfriend's license plate on fire, local police told several media outlets.

Bethany Carlson on Friday got the call that Leslie Rosario, 31, left baby Frankie in the Route 17 Sheraton Hotel Oct. 5 while she attempted to torch her former flame's Mercedes-Benz, the New York Post reports.

The Carlsons had been paying $35 monthly to Sittercity.com for Rosario's services and say they were told she had been verified with references, according to the article.

Rosario gave police a fake name at the time and then days later, claimed she had been robbed at gunpoint when she failed to show up at the Carlson's for work, The Post reports.

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