The mother of a Southern California says the deputies who beat her son after a horse pursuit caught on camera by NewsChopper4 acted like they were on a "joyride."

Anne Clemenson said Thursday night she still does not know where her son Francis Pusok is, or what condition he is in following the arrest, which took place in the Deep Creek area of Apple Valley Thursday.

She was shocked at the way the San Bernardino County sheriff's deputies beat her son, appearing to kick him 17 times, punch him 37 times and hit him with batons four times. NBC4 reviewed the video multiple times.

"To me, it was like a joyride for the cops to do this to him. (It was) brutality. He didn't deserve something like that," Clemenson said. "To Tase him, the beatings that I see them doing to him — it's uncalled for. You see him laying down, and they continue to kick him, hitting him and punching him. Why?"

Clemenson was desperate to find out how her son was doing in hospital, but Thursday night still did not know where he was.

"All I want to know is, where is my son, and is he OK? I think something's happened to him, and they're not telling us," Clemenson said.

She questioned the officers' behavior, and said she did not believe they would have acted like that if they had known their actions were being captured on camera.

"To me, if they think they are not being watched, they can get away with whatever they want and do what they want to anybody," Clemenson said.

Clemenson was also angry her son did not receive treatment before the deputies.

"My son should have come first because of what they did to him. He was down, they are walking around like nothing happened and everything is OK," Clemenson said. "They come first before someone who's down on the ground and the way they kicked and beat at him."

San Bernardino County Sheriff John McMahon ordered an immediate internal investigation Thursday into the arrest by deputies after a horse pursuit caught on camera by NewsChopper4.

"I'm not sure if there was a struggle with the suspect," McMahon said. "It appears there was in the early parts of the video. What happens afterwards, I'm not sure of but we will investigate it thoroughly."