A teenager, who mowed down an elderly woman gardening outside her home in Hempstead Tuesday morning, was apparently high on prescription drugs during the time of the accident.

Kayla Gerdes, 18, of Freeport lost control of the van she was driving and crashed onto the lawn of a house on Cathedral Avenue, killing 69-year-old Rebecca Twine-Wright, according to Nassau County police.

Gerdes admitted to reporters she was on prescription drugs when she was taken from Nassau County police headquarters Tuesday morning.

"It was an accident ... please leave me alone," Gerdes shouted as she left the building.

The teenager apparently told authorities she was high on Oxycodine. In addition, Gerdes blamed the fatal accident on a vehicle malfunction.

"The car went out of control," she yelled at reporters. "I was pressing the brake and it wouldn't go!"

According to police, she was the passenger in the work van, but insisted on driving because she felt as though her fellow employee was traveling too slow.

Gerdes pleaded not guilty to charges of second-degree manslaughter, unlicensed operation of a motor vehicle and driving while ability impaired by drugs. She is being held on $200,000 bond or $100,000 bail and is due to appear before a judge on Friday.