NEW YORK (CBSNewYork) — A 2-year-old boy was found dead in a Midtown restaurant bathroom Monday afternoon, and his mother, who had been with him, was in custody.

As CBS2’s Tony Aiello reported, the stroller that brought little Gavriel Ortiz to the place where he died became a piece of evidence in the case police were building against his mother – Latisha Fisher, 35.

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Police said she locked herself in the bathroom with the boy around 2:25 p.m. at 5 Boro Burger, at 80 W. 36th St. at Sixth Avenue.

First a customer, then an employee tried to get the woman to leave the bathroom, but she refused, 1010 WINS’ Al Jones reported.

When asked what she was doing, the woman allegedly said, “I put my hand over his mouth to put him to sleep,” WCBS 880’s Marla Diamond reported.

Workers at the restaurant gained entry with a key and found the boy unconscious and foaming at the mouth, police sources said.

Chris Coffee was one of the witnesses inside 5 Boro Burger after the boy was removed from the bathroom.

“Hear a little commotion in the corner, get up, see boy sitting there, like, kind of unresponsive looking,” Coffee said. “Staff is talking about how this woman’s in the bathroom, and how she won’t come out; she’s locked herself in.”

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Sources said the boy’s mother later said, “The devil made me do it.”

The child was rushed to Bellevue Hospital Center, where he was pronounced dead on arrival. The mother was taken into custody and transported to the Midtown South Precinct, Jones reported.

“The mother came out in handcuffs. She was inside the restaurant with the baby. She didn’t seem to distressed, just kind of had her head down,” witness Marcus Como told Jones.

A police officer late Monday was guarding the door to Fisher’s apartment at the Gompers Houses on the Lower East Side.

“Adorable little boy,” said Carolyn Lawson, a neighbor of Fisher’s. “I don’t understand what, you know, goes through people’s minds sometimes.”

Several detectives also visited to conduct interviews and gather evidence.

“Anytime I’ve seen her around, you know, she was happy pushing the baby with the father and everything, and I guess you just never know what goes on,” Lawson said.

Police also spent hours taking statements from witnesses at the restaurant – a popular spot that turned away dozens of diners who were shocked to learn why.

“Sounds very terrible,” said Ken Nys, a visitor from Belgium. “We’re just tourists. We’re trying to get in. So we’re glad we weren’t in there when it happened.”

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Police late Monday were waiting for the New York City Medical Examiner’s office to release autopsy results for the boy as they questioned his mother.