Kerry Kennedy, NY Gov. Andrew Cuomo's ex-wife and the seventh of 11 children of the late Sen. Robert F. Kennedy, has been arrested for driving while impaired by drugs.

Kennedy accidentally struck a tractor-trailer and fled on Friday, the Associated Press quoted state police as saying.

She was found in her car on the side of a road in Westchester, just north of New York City, near where she lives in Bedford, with a flat tire.

Callers to 911 had reported her car driving erratically on Interstate 684 before it collided with a tractor-trailer in the town of North Castle. 

However, a spokesman for Kennedy, 52 — mother of three daughters to Cuomo — denied that she was driving under the influence of drugs, according to USA Today.

"Kerry Kennedy voluntarily took breathalyzer, blood and urine tests — all of which showed no drugs or alcohol whatsoever in her system. The charges were filed before the test results were available," said Ken Sunshine.

And the New York Post cited a source as saying that Kennedy "may have had some sort of seizure" and doesn't remember the rush-hour drive on I-684.

“This is terrifying for her because she doesn’t know why it happened,” the source said, adding that the family feared she may have an undiagnosed medical condition.

The family source said Kennedy told cops she "may" have taken Ambien.

The Post pointed out that Kennedy's cousin Patrick, admitted to driving while impaired on the drug, used to treat insomnia, in May 2006.

The then-Rhode Island congressman pleaded guilty to drugged driving after crashing his car in Washington, DC. 

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