It happened around 1 p.m. near the intersection of 14th Avenue and Jones Street in Newark.
Law enforcement sources tell WABC-TV that the female bus driver was on heroin and crashed the occupied bus into a tree.
Video obtained exclusively by WABC-TV shows the bus moving slowly through an intersection, passing in front of cars before jumping the curb and hitting the small tree.
Twelve students between the ages of 5 and 13 were on board at the time.
They were evaluated by EMS, and no injuries were reported.
Police say the driver is at the hospital pending a search warrant for her blood. She has been charged with twelve counts of endangering the welfare of a child, along with possession of drug paraphernalia and driving while impaired.
Witness Sherod Jones says he jumped on the bus to attend to the driver and the kids.
"I got on the bus, and I checked to see what the lady's foot on the brake, and I put it in park so that the kids would be alright," he said. "They said it was 12 kids on that bus, so I just wanted to make sure that the lady was alright. She was really my main concern."
He said he was skeptical the woman was on drugs.
"It looked like she was having a stroke or something, or a heart attack or something," he said. "She was stuck. When that bus started to move, you saw the lady's arms going down slow, like if she was coming out of it, the lady's eyes were wide open."
According to the Newark School District, the bus was coming from the Fourteenth Avenue Elementary School.
Officials said the district will be taking over all school bus routes immediately until the investigation is concluded.
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