Officials in Rio Vista, California, have launched an internal investigation into whether a member of the Rio Vista Police Department used excessive force when he body slammed a Black woman to the ground, NBC affiliate KCRA reports.

According to Rio Vista Police Chief Dan Dailey, a car was pulled over in a routine traffic stop on Sunday, reportedly for a suspended registration, and all four occupants in the car were detained because they refused to exit the vehicle.

Tyrone Clayton Jr., a passenger in the car, called his family to the crime scene to capture the incident with their phones. His stepsister, Cherish Thomas, and stepmother, Deshauuna Payne, arrived on the scene and began recording the interaction. An altercation between the bystanders and police began shortly afterward.

According to Dailey, both women obstructed the investigation; Thomas pushed one officer and Payne attempted to hit another. In the midst of the scuffle, Thomas, 32, was slammed to the ground.

Dailey said, "[The] officer tackled her to the ground in order to gain control of her while his partner stepped in to take Deshauuna Payne into custody."

Thomas denied ever pushing the officer. "What can I do at this point? He's a police officer. And I'm [120 pounds]," she told the local television news station. "So what am I going to do? Fight him? No."

Payne also denied any wrongdoing. "I wasn't trying to attack them. He slammed my baby," she explained. "I went in mother mode to protect my child."

Thomas was treated for injuries at a local hospital and released on Monday. She accused the officer of slamming her head into the ground and claimed she's experienced headaches, sore legs and arms after the incident.

Despite the video footage that has circulated online, Dailey claimed body camera footage from the officers will "show the totality of this situation."

He also said an additional car of "confrontational and uncooperative" family members arrived on the scene that required officers to request assistance from the Solano and Sacramento County sheriff offices.

Both women have been charged with resisting arrest and obstructing an investigation.