MISSION VIEJO (CBSLA) – A bystander is being thanked for helping a deputy arrest a bloody and sweaty DUI driver after the suspect was involved in a head-on collision.

The good Samaritan captured the incident on cell phone video after he happened upon the crash in Mission Viejo.

READ MORE: New COVID-19 Variant Raising Alarms, Restrictions

The Orange County Sheriff’s Department said the suspect took off running while first responders helped a mother and son injured in the crash.

Deputy Olivia Coco was first on the scene and chased after the suspect, 28-year-old Richard Lopez.

The good Samaritan said he ran too and started shooting the take down with his phone. But he quickly realized the deputy needed assistance.

“You want help?” he asked.

“Yeah, dude,” Coco replied.

The bystander said the man was “incoherently flailing around.”

READ MORE: Black Friday: Another High-End Store Is Robbed, Prompting LAPD To Issue City-Wide Tactical Alert

In the video, the man appears to be struggling with Coco on a sidewalk.

“He’s covered in blood and sweat, obviously, from the collision, so it’s kind of hard to get ahold of him,” Coco said. “His shirt is, you know, kind of torn and coming off, so it’s kind of a struggle just because of the blood and stuff on his body.”

The good Samaritan dropped his cell phone and ran to help.

“I never had anybody ask if I needed assistance, or anything like that. So it was nice to have someone not just stand there and film all the time and, you know, actually kind of step up and help out.

The hit-and-run driver was taken into custody on suspicion of DUI and evading police.

The mother and child were treated and released from a local hospital with non-life threatening injuries.

“Never during my years of service has any citizen ever asked to help me. Instead of foolishly putting himself in harm’s way, he asked the officer if he could help her,” said Sgt. Pax Perez.

MORE NEWS: Man Struck, Killed In Harvard Heights Hit-And-Run

Sheriff’s deputies said they’re grateful for the help, but Coco noted she accepted the offer for help because she knew the suspect was unarmed.