OTTAWA -- Prime Minister Justin Trudeau says, after watching newly released video of the violent arrest of a First Nations Chief by RCMP in Alberta, he has "serious questions" about what happened and is urging swift action on police reform.

In footage of the arrest of Athabasca Chipewyan First Nation Chief Allan Adam obtained by CTV News, an RCMP officer is seen tackling him to the ground and punching him, after the chief was confronted outside a casino in Fort McMurray, Alberta, about an expired licence plate tag.

Chief Adams has alleged racism and police brutality. Despite an earlier RCMP account that officers acted reasonably, the incident is now under investigation by Alberta’s Serious Incident Response Team.

The prime minister on Friday said it’s vital the investigation be "open, transparent, and independent."

"I think we’ve seen examples of systemic discrimination, systemic racism in the past days in many different ways and that’s why we need to address it seriously," he said. "We need to look at the entire system to improve it, to make sure situations like this don’t happen in the future."

Trudeau said this incident is not an isolated event.

"Far too many Black Canadians and Indigenous people do not feel safe around police. It’s unacceptable. And as governments, we have to change that," said Trudeau.

The prime minister said he raised the issue during his weekly call with premiers Thursday evening.

"I raised with them some of the ways we can work together moving forward, including on practical things like the adoption of body cameras. This is something I’ve already discussed with RCMP Commissioner Lucki. But reforms are needed at all levels of policing, and these reforms need to happen quickly."

This follows comments by the RCMP Commissioner on Wednesday that she “struggles” with the term systemic racism because she’s seen a variety of definitions, but noted the national police force is not immune to "unconscious bias."

Earlier this week, Alberta RCMP Deputy Commissioner Curtis Zablocki denied the presence of systemic racism in policing in Canada.

Both commissioners on Friday walked back their statements and have acknowledged its existence.

"I did acknowledge that we, like others, have racism in our organization, but I did not say definitively that systemic racism exists in the RCMP. I should have," said Lucki.

Zablocki said he was enlightened after speaking with community members and doing his own research.

"For me it was really getting a better perspective on what systemic racism is. As I’m sure you’re aware, there are many types of racism terms and categories, as I did some research and goggling it, it just became clear," he said.

Conservative Leader Andrew Scheer first responded to the video on Twitter, saying he is "deeply disturbed” and that “excessive use of force is always wrong."

On Friday, he told reporters he feels strongly about the use of dashcams and body cameras to keep police officers accountable.

He said the Liberal government has done nothing to address a backlog of complaints about the RCMP.

"If Justin Trudeau has done nothing about these types of things, and he’s indicated there are issues with the RCMP with systemic racism, precisely what is he going to do about it?" he said. "With Mr. Trudeau we see these empty words without any action to back it up, it’s very frustrating."

Mi'kmaq lawyer, professor and activist Pam Palmater told CTVNews.ca she questions Trudeau’s pledge to undergo reforms in the policing sector in Canada now, given there’s been little action until this point.

"He’s got a real problem. He needs to look at this from a national public safety crisis issue and he and his cabinet need to sit down and really take a good hard look at all the recommendations that have ever been made in justice inquiries talking about racism in the RCMP," she said.

"They just ignore it time and time again."

She said his response on Friday that many Canadians are for the first time learning about systemic racism this week, disregards past efforts by anti-racism activists to inform society about these issues.

"It defies every justice inquiry that’s ever been held, published, televised. It defies all of the social surveys that have ever been done about Canadians who realize that there’s racism, especially against Indigenous Peoples. It literally defies logic,” she said. “He knows better, don’t tell me he doesn’t know better."

The nearly 12-minute long video is critical, she says, in helping people understand the situation.

"This video is one incident but it is representative of the thousands of incidents that have happened to us but we were never believed. We were charged, we were imprisoned and there was no social media, no cell phones to capture the brutal beatings."

With files from CTV News' Adam Frisk and Ben Cousins, and CTV Edmonton's Laine Mitchell