This is the shocking moment a Houston mother appears to run over and kill her three-year-old son during a game of chicken.

Lexus Stagg, 26, is charged with criminally negligent homicide after horrifying security footage appeared to show her driving forward as her three young children tried to run away from her 5,600 pound SUV.

Police say Stagg had claimed she had not seen the boy who 'ran behind her vehicle as she backed out of her parking spot'.

And law enforcement had originally called his death an 'unfortunate accident' after she is said to have told them she thought she had hit a speed bump.

But security footage shot from a nearby property on June 11 looks to show the mother reversing back as her three young children run after her car.

Footage shows the driver then pulls forward as the youngsters try to run out of the way of the vehicle.

Two manage to flee the car but her young son, named locally as Renfro, is hit before being run over twice, according to police.

Lexus Stagg, 26, is charged with criminally negligent homicide after police say she ran over and killed her three-year-old son during a game of chicken on June 11 in Houston

Security footage shot from a nearby property appears to show the mother reversing back as her three young children run after her car. Footage shows the driver then pulls forward as the youngsters try to run out of the way of the vehicle and one is hit

Court documents state the boy was caught under the right tire but she continued to drive forward, running him over again.

The three-year-old was rushed to hospital where he died.

District Attorney Kim Ogg said: 'Every parent has an obligation to protect their children, even from themselves.

'Car's aren't toys and playing chicken with your kids isn't a game.'

Sean Teare, chief of the Vehicular Crimes Division, said: 'You should be playing Peek-A-Boo with a 3-year-old instead of forcing him to try and dodge a 5,600 pound deadly weapon.'

He added: 'She was in her car and her children were playing in front of her in the parking lot. She put her car into reverse, and drove at least 100 feet.

'The three kids followed her, followed the car, at which point, the defendant put her car into drive and drove toward her children as they were running toward her.

'The two older children were able to get out of the way, and tragically, the younger child was not and was run over by two of her tires.'

Stagg - who faces up to ten years in jail if convicted and has a history with Child Protective Services - had her bail set at $1,500. Her two other children have been placed with relatives

Stagg - who faces up to ten years in jail if convicted and has a history with Child Protective Services - had her bail set at $1,500.

Her two other children have now been placed with relatives.

Neighbor Walter Turcios told ABC13: 'I felt bad, because those parents, they were never there, they were kind of negligent. (The kids were) always out here without supervision.'