Editor's note: An earlier version of this story said Nathan Phillips was a Vietnam veteran. He served in the U.S. Marines but was not deployed to Vietnam.

Covington Catholic High School has said that students could be expelled after a video went viral, showing an incident where students who were in Washington D.C. for the March for Life interacted with indigenous marchers at a different event.

Multiple videos have gained popularity, including a longer version that shows the start of the incident. Many people said the longer videos show that the students were initially provoked.

Analysis:What the video from incident at the Indigenous Peoples March tell us about what happened

Who's who:Key players in the confrontation between demonstrators and CovCath students in Washington

Original reporting:NKY Catholic school faces backlash after video of incident at Indigenous Peoples March surfaces

PX column:Know what else is embarrassing about Covington Catholic incident? Knee-jerk reaction

Here's what we know about the incident and what happened leading up to it.

What happened?

Multiple videos circulating on social media show a group of boys from Covington Catholic High School around a man at the Indigenous Peoples March in Washington D.C. The man initally approached the students.

Officials have confirmed that those students were from Covington Catholic.

One video shows a young man wearing a "Make America Great Again" cap standing near to and staring at a man who is drumming as other young men surround the two.

The Indigenous Peoples March and the March for Life both occurred on Friday.

Who was involved?

The Native American man in the video was identified as Nathan Phillips, a veteran and Native American elder of the Omaha tribe, by Indian Country Today.

Chase Iron Eyes, a spokesman for the Indigenous Peoples March and an attorney for the Lakota People's Law Project, said by phone Saturday that Phillips initially approached the students in an attempt to defuse the situation.

But he was quickly swarmed, Iron Eyes said.

Some video from the event counters that contention, showing Phillips walk into the crowd of students.

The students involved have not yet been identified but the Catholic Diocese of Covington confirmed that the students involved were from Covington Catholic who were there for the March for Life.

Longer videos show the start of the incident

Phillips said the incident started as a group of Catholic students from Kentucky were observing a group of Black Israelites talk, and started to get upset at their speeches.

Phillips said some of the members of the Black Hebrew group were also acting up, "saying some harsh things" and that one member spit in the direction of the Catholic students. "So I put myself in between that, between a rock and hard place," he said.

More:Native American leader of Michigan: 'Mob mentality' in students was 'scary'

Why were students in D.C.?

Students from Covington Catholic accompanied a large group from the Roman Catholic Diocese of Covington to the March for Life that took place in Washington D.C. on Friday.

The school's website said students planned to attend the March for Life event, held Friday in Washington, D.C., the same day as the Indigenous Peoples March.

According to a post from Newport Central Catholic, another local Catholic school, more than 1,000 people went to D.C. for the march.

School officials say expulsion is on the table

Laura Keener, the communications director with the Roman Catholic Diocese of Covington, released a statement Saturday afternoon:

"We condemn the actions of the Covington Catholic High School students towards Nathan Phillips specifically, and Native Americans in general, Jan. 18, after the March for Life, in Washington, D.C. We extend our deepest apologies to Mr. Phillips. This behavior is opposed to the Church’s teachings on the dignity and respect of the human person," the statement said.

She said the incident is being investigated and that students could be expelled or otherwise punished. There is no word on if Covington Catholic staff were with the students and if they face discipline.

More:March for Life: Cincinnatians among the thousands in Washington

What is Covington Catholic?

Covington Catholic is a private all-boys high school in Park Hills, Kentucky.

Covington Catholic serves grades 9-12 with an enrollment of about 585 students and 42 teachers, according to the diocese. Tuition for the 2018-2019 school year was $7,950.

According to the school, the 213 students went to the March for Life in 2017. The school said 84 students went in 2008. The trip for students is $130.

"On a daily basis our students are given opportunities to live their faith. They include inserting the words 'born and unborn' at the end of the Pledge of Allegiance," a letter to parents said. "Once again this year we offer our students the opportunity to participate in this most worthwhile event, the 46th anniversary of the March for Life, demonstrating our support for all Life, 'born and unborn.'"

More:Ex-Xavier commit, former Covington Catholic hoops star Jake Walter charged with rape, sodomy

A Change.org petition has been started

A Change.com petition addressed to Rev. Roger Joseph Foys, Bishop of the Roman Catholic Diocese of Covington, has asked for the school to stop any association with the March for Life following the event.

The petition, signed by 1,480 people, asked for the immediate termination of principal Robert Rowe for "fostering an environment where these types of actions and words are condoned." The petition was penned by Matthew Lehman, who said he is a 1995 graduate of Covington Catholic.

The petition also asked for the appointment of a board of the school to review CovCath’s admissions, educational standards, administration and social mission.

"I have watched with concern over the years as CovCath has become less diverse, more elite, and more expensive - even as the surrounding community has become more economically and ethnically diverse," Lehman said. "It is abundantly clear that CovCath has lost its way under current leadership and significant changes need to be made at the institution."

Covington mayor speaks out

Covington Mayor Joe Meyer called the confrontation "disturbing, discouraging, and - frankly - appalling" in an op-ed Saturday.

"The point is that because of the actions of people who live in Northern Kentucky, our region is being challenged again to examine our core identities, values, and beliefs," Meyer said.

"No, we’re not perfect. More progress needs to be made, and we will continue to work diligently on making it. In the meantime, Covington is proud of being a welcoming city where bigotry, discrimination and hatred will not be tolerated."

More:Covington Mayor Joe Meyer: March confrontation doesn’t represent city’s values