A video that went viral Monday showed Los Angeles County sheriff's deputies detaining three Black teens at gunpoint after witnesses say they had called police to report that a man armed with a knife was chasing the boys.

The video, which was originally posted on Instagram by the mother of one of the boys, showed a tense situation in Santa Clarita where the three were handcuffed one by one with firearms pointed in their direction as bystanders pleaded with deputies to deescalate the situation, asserting that they were actually the victims.

"It’s not them," multiple people are heard yelling.

"Put your guns down. They’re kids," another person says. "They weren't doing anything."

Another woman is heard telling the teens to "keep your hands up" and "put your hands up." The three young men, whose exact ages were not known, are seen in the video walking backward one at a time toward deputies, who then handcuff them and place them in squad cars.

A woman who identifies herself as the manager of the nearby Buffalo Wild Wings tells the deputies that she is the one who called 911, saying she reported that "there is a male Hispanic outside the parking lot chasing three African American kids with a knife."

"There's a crazy man running around our parking lot chasing kids, trying to stab them, and you come here and approach the kids that we're trying to help like that with guns," she says. "And the crazy man is running down the street with a knife."

and says, "so this seems like a different call," saying that they were responding to a call for service about someone being hit with a skateboard.

"These three gentlemen were described in the call," he says. "We’re on a different call."

A sheriff's department spokesperson said a call of an “assault with a deadly weapon - just occurred” was received on Friday at about 5 p.m.

The informant said that two Black men in their early 20s hit another man in the head with a skateboard. When deputies arrived to the location, they found two males matching the description provided by the caller, the spokesperson said. No arrests were made after the men were detained.

In a message posted to Facebook Monday afternoon, Sheriff Alex Villanueva said he was aware of the video and had "concerns regarding the tactics employed."

"A call for service was received regarding a felony assault and the deputies detained those alleged to be involved," Villanueva said. "The matter is currently being investigated."

No additional information was provided about the incident.

Santa Clarita Mayor Cameron Smyth also released a statement, saying the city was "very concerned" about the footage and had asked that the internal review be expedited

Tammi Collins, who posted the original video on Instagram, wrote that her son and two of his friends were sitting at a bus stop when they were attacked by "a gentleman (homeless guy) who approached them and first asked them if they had any crack then tried to take their things."

"The guy became so aggressive that he took his shirt off pulled out a knife and whip and [then] tried to stabbed them," Collins said. "His friends only had their skate boards to cover them from the knife and whip so they held it out to keep distance from this guy."

Collins did not respond to a request for comment. But in her post, she expressed concern about how her son and his friends will recover from the "traumatic experience."

"This is something my son and his friends will never forget," she said.