"It was absolutely the most terrible thing I've ever witnessed", said Brittany Caine-Conley, the lead organizer with Congregate Charlottesville. The group carried torches at a rally Friday night.
However, the event was shut down by authorities in the early afternoon.
Videos show the silver auto reversing and fleeing from the scene with a windshield covered in what appears to be blood. Virginia State Police confirmed two fatalities as a result of a helicopter crash southwest of Charlottesville Saturday but it was not immediately clear whether these were the fatalities being referenced by McAuliffe and Jones.
Warning: The video contains graphic images.
The driver of the Challenger was taken into custody and charges were pending, said Al Thomas, the Charlottesville police chief.
His alleged action led to the death of a yet to be identified 32 year old woman and several critical injuries.
President Donald Trump tweeted his condolences to the family of the woman Saturday evening, adding his "best regards to all of those injured".
White supremacists clashed with counter protesters during the "Unite the Right" rally, which was protesting the proposed removal of a Confederate General Robert E. Lee.
The park was renamed Emancipation Park in June.