LOWELL (CBS) — A 4-year-old out trick-or-treating was hit by a car Monday night, police say.

The child was out trick-or-treating with his mother when a woman driving near 52 Marshall Ave. at 7:18 p.m. struck him with her car, police said.

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The woman, who had two kids in the car at the time of the accident, stopped and got out of her car to talk to a witness after she hit the boy. She saw the boy lying in the street, but she then got back in her car and drove away, police say.

Hundreds of kids were trick-or-treating in the neighborhood at the time.

The driver was also out to trick or treat when she struck the boy, according to police. A witness followed her when she left the scene, but it was police who eventually tracked her down.

The boy was taken to Lowell General Hospital with a serious head laceration, police say. He was alert when he was taken to the hospital.

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Police tracked the hit-and-run driver down nearby. (WBZ-TV)

Police tracked the hit-and-run driver down nearby. (WBZ-TV)

Stephen Fay was driving just behind the car that hit the boy.

“I saw the car go right over the kid and I saw the kid laying on the ground,” Fay said. “Then the car stopped and people started screaming and someone said call 911.”

Fay said the cars were driving very slowly down the street.

As soon as the child was hit, Fay said people started screaming and many called 911. He described the scene as surreal.

Fay said he did not see the driver leave the scene because he was consumed with calling 911, but he noted the driver did stop immediately following the crash.

The car involved in the crash was taken into custody and the driver was questioned by Lowell police Monday night. Police say the woman will be charged, but it’s currently unclear what those charges will be.

Alcohol and speed are not currently factors in the crash, police say.

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