Hundreds in a Los Angeles County neighborhood took to the streets to protest after immigration agents detained a 20-year-old outside a Pico Rivera Walmart on Tuesday.

The young man who was wrestled to the ground, Adrian Andrew Martinez, is a U.S. citizen, according to his family.

A video of the incident shows Martinez, in a blue Walmart vest, appearing to talk to the Customs and Border Patrol agents before one of them pushed him back. In the middle of the exchange, the man who was recording, Oscar Preciado, had his phone knocked out of his hand. 

After picking it up to start recording again, Preciado captured the federal agents wrestling Martinez to the ground. Preciado said the agents tried to grab him, too. 

"He grabbed me by the neck and put the other hand behind my leg," Preciado said. "Luckily, I was able to get him off of me and kept recording ... I told him I'm recording this and that's when he smacked my hand to get my phone out of my hand."

According to Preciado, the encounter with immigration agents happened in a Walmart parking lot on Washington Boulevard after Martinez stood up for an older man federal agents had detained. Martinez insisted they needed a warrant to arrest the man. Preciado added that he only saw Martinez talking to the agents. 

Preciado works for a delivery service and talks to Martinez every day while picking up orders at Walmart. He recalled a crowd shouting, "he's a U.S. citizen," while agents arrested Martinez. 

"They kept trying to get us back away when they realized there was like 10 of us that were recording," Preciado said. "Some other guys from an unmarked vehicle came out of it with their guns in their hands, pointing at us and everything."

Martinez's family said they don't know where federal agents took the 20-year-old. They went to a federal detention center and were told he was not there, but that he is likely going to be charged with assaulting a federal officer.

KCAL News has reached out to Immigration and Customs Enforcement and Walmart for comment, but has not received responses. 

On Wednesday, that Martinez "was arrested for an allegation of punching a border patrol agent in the face after he attempted to impede their immigration enforcement operation."

"I will repeat, if you impede our agents or strike them, you will end up in handcuffs facing federal criminal charges. Don't do it," Essayli wrote.