The officer had no knowledge of what had happened, and the 32-year-old driver told first responders that she didn't, either, according to Assistant Fire Chief Erik Kalapir.
She had been making a u-turn in the back area before finding herself in the embankment, he said.
The woman reported no injuries but was taken to St. Vincent's Hospital for an evaluation, he said.
The cause of the accident was still under investigation.
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