NEWBURGH, NY (CBS) — Police say Lashandra Armstrong was a single mother, with a history of domestic problems with the father of three of her children. Investigators say they are still trying to figure out why she would intentionally drive into the Hudson River with her children in the car.

“I can’t imagine. It breaks my heart. It’s an awful, awful thing,” said one Newburgh resident.

That’s how many feel in the Orange County town 60 miles north of Manhattan.

Relatives shed tears where, police say, Tuesday night Armstrong drove the family van with all four kids into the Hudson River. The family’s neighbors were stunned by the news.

“She was a good mom to her kids, so I don’t know. I’m in shock,” said Armstrong’s neighbor.

Authorities say Armstrong’s 10-year-old was able to climb out a window before the can sunk. A woman picked him up and took him to a nearby firehouse. (CBSNY’s Continuing Coverage)

Fire chief Mike Vatter says, “He was obviously shaken up, having a difficult time explaining what happened, he was soaking wet. The river this time of year is about 40, 45 degrees.

When rescue units got to the scene, Armstrong and the three remaining children, ages five, two months and 11 months old, were all dead. Police say, moments before ttheir deaths, they got a phone call that Armstrong was involved in a domestic dispute.

“The belief was based on a phone call that the relative received, where they stated they heard tussling in the background and a history of domestic problems in the past,” said Newburgh Police Chief Michael Farrara.

Police are still investigating, but what would cause a parent to try to kill all four of their children? A local clinical psychologist doesn’t know the particulars of the case, but she says a number of things, including stress, substance abuse, or even postpartum depression could have played a role.

“We’re concerned that her problem solving, her thinking was way beyond her ability to cope. It raises questions about her mental health status, or where a woman’s mental health status is at the time and the months and years before (having children),” Dr. Helen Coons.

Lashandra Armstrong lived six blocks from the Hudson River.

When she picked up her children from day care Tuesday, workers say she appeared stressed but not depressed. One said it just seemed like she was having a bad day.

Reported by Dave Huddleston, CBS 3

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