Video courtesy of CNN

PALM BEACH (KRON) — Newly-released dash cam video shows the arrest of a woman, driving erratically with a toddler inside the car.An attentive tow truck driver saw the dangerous driving and called police.

He stayed on the phone with an emergency dispatcher until deputies arrived at Belvedere and Haverhill roads.

A deputy arrives, sirens blare, and the woman pulls over.

He talks to the driver, Brandy Lerma for nearly 20 minutes.

Back-up arrives and a toddler is taken out of the car.

Then Lerma took a series of sobriety tests.

First, the deputy asks Lerma to follow his pen with her eyes, but she can’t stand still and stumbles to the side.

Next, she’s instructed to walk down the white line.

She fails this test and another, until she is ultimately cuffed and taken to jail.

The video shows her screaming in the back of the patrol car and telling the officer “I will kill you.”

In addition to DUI-related charges, Lerma also faces a charge of child abuse.CNN contributed to this article.