Hudson River, officials said.
Only the dead woman's 10-year-old son escaped the death vehicle on Tuesday night, leaving the mom to drown with her sons, ages 2 and 5, and her 11-month-old daughter, officials said.
The surviving son managed to open a power window, slip out and swim safely to shore through the 45-degree water.
A passing good Samaritan picked up the soaking wet boy and drove him two blocks to a local firehouse, where the shivering child - with great difficulty - detailed the gruesome scene.
"We're talking about a tragedy in this city that is second to none," said Newburgh Mayor Nick Valentine.
The distraught driver was identified as Lashanda Armstrong, 25. The landlord at her building said Armstrong shared the apartment with her boyfriend, and had twice asked to get the locks changed in a six-month period - most recently in March.
"She said she didn't want him here," John Boubaris, 48, said. "That was the last person living with her, the boyfriend."
Neighbors identified the boyfriend as Jean Pierre, the father of the three dead children. Read More
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