The Los Angeles County Sheriff’s Department has opened an internal investigation into the arrest of a sexual assault suspect that was captured on video in downtown Los Angeles.

The video, obtained by NBC4 from sister station Telemundo, shows what appears to be a deputy stomping on the head of 31-year-old Alexis Torres. The suspect was arrested Friday morning for allegedly groping a woman near First and Hill.

The department is aware of the video and launched an internal investigation before having seen the footage, according LA County Sheriff’s Department spokesman Steve Whitmore.

That deputy, a 24-year veteran with the department, has been suspended with pay, Whitmore told NBC4. The department won’t comment on the video, he added.

NBC4 showed the video to retired FBI special agent James Graham, who investigated allegations of police abuse for more than 20 years.

“It appears to me there was sufficient law enforcement present to keep him under control without the kick to the head,” said Graham.

Maria Sorto, Torres' mother, cried when she watched the video of her son's arrest and says she's worried for her son who she says suffers from depression, anxiety and other mental illnesses.

Torres -- who Sorto says recently changed his medication -- is being housed in a separate unit for inmates with medical conditions, sheriff's officials said.

Torres' family say they haven't been able to see the 31-year-old man since the incident.

"They told us he was sent to the USC medical center so that we were not able to see him so since he was arrested we were not able to see him," said Maribel Aviles, family friend.

Torres and all three arresting deputies reportedly suffered injuries.

"Two men were already on top of him so I don't see why he needed to be hit with the foot on his head. I don't think that's right," Aviles said.

Torres was in jail Monday night on suspicion of battery and possessing fake identification. Arraignment was scheduled for Tuesday morning, but was postponed pending the investigation.

A Telemundo crew was working on another story in the area when the arrest occurred.

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