Video of a Texas police officer wrestling a 15-year-old Black girl to the ground and drawing his gun on several other Black teenagers has spread like wildfire on social media.

The officer, Eric Casebolt, is on administrative leave as officials investigate why a call to deal with alleged unruly teenagers at a pool party in McKinney, a city in the Dallas-Fort Worth metroplex, escalated to the intense situation seen on the video, which has nearly 4.4 million YouTube views on Monday morning.

What exactly happened?

The McKinney police chief told the Dallas Morning News that three officers responded to a call from a private security guard at a neighborhood pool that is only open to residents of that neighborhood. The guard told police that unauthorized teenagers were using the pool and refusing to leave. There was also a report of teenagers fighting.

Buzzfeed News reports, though, that there was a fight between adults and teenagers resulting from racist comments made by white adults to the Black youths, who were allegedly told "to leave the area and 'return to Section 8 [public] housing.'" Brandon Brooks, the white teenager who shot the video, told Buzzfeed that there was a pool party and that "many students had arrived at the end-of-school celebration at the pool on guest passes" and "[s]ome had also jumped over the fence."

“I think a bunch of white parents were angry that a bunch of black kids who don’t live in the neighborhood were in the pool,” Brooks said.

The video has also led to debate about whether Casebolt used excessive force when he pinned one teenager to the ground and pointed his gun at several others.

After seeing the video, one Dallas criminal defense attorney and former McKinney police officer told the Morning News that the incident was "a classic example of how something can escalate out of control very quickly by the actions of the officers, not by what was going on.” CNN's law enforcement analyst sided with the officer. "I thought the kids were not compliant whatsoever," said Cedric Alexander, who is the public safety director of DeKalb County, Ga. "That in itself is a problem. Those kids attempted to overtalk the police."

Zahid Arab, a reporter for the local Fox affiliate, tweeted a photo of a sign that has been posted at the pool in support of the police officers:

Social media has reacted to the video.

As the video spread, people starting to weigh in on the officer's actions.

Filmmaker (and "Selma" director) Ava DuVernay contrasted the McKinney police's rough handling of the teenagers with the relatively laid back approach of police officers in Waco, Texas during a biker gang fight that left multiple people dead:

We also heard from Black Lives Matter leaders Shaun King, Deray McKesson, and Johnetta Elzie: