Canadian Prime Minister Justin Trudeau on Friday called for an independent investigation after a "shocking" video showing the arrest of an indigenous chief by federal police.

The video, filmed and released by the Royal Canadian Mounted Police, show an officer rushing at Chief Allan Adam on March 10 during an encounter over an expired license plate. The officer tackles Adam and punches him in the face.

'Not an isolated incident'

"We've all now seen the shocking video of Chief Adam's arrest and we must get to the bottom of this," Trudeau told a daily briefing.

"Like many people I have serious questions about what happened," he said. "The independent investigation must be transparent and be carried out so that we get answers."

In the dashcam video, broadcast by several Canadian media, Adam has a heated exchange with a police officer outside a casino in the province of Alberta.

The tense situation degenerates quickly when the officer tries to handcuff Adam's wife, and a second officer is seen tackling Adam to the ground and punching him in the face.

Adam last weekend circulated images of his bruised and battered face following the arrest. 

"We know that this is not an isolated incident," Trudeau said. "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."

Black Lives Matter demonstrations

Thousands of Canadians have marched in solidarity with US protesters against racism and police brutality, following the death of George Floyd, an unarmed black man, during an arrest by Minneapolis police.

Trudeau himself took a knee, a popular protest gesture, last Friday at a demonstration outside his office in Ottawa.

On Thursday, the prime minister said systemic racism exists in all Canadian institutions including the RCMP, after the nation's top cop balked at the notion.

After a week of denying it, RCMP Commissioner Brenda Lucki on Friday reversed her position and acknowledged in a statement that "systemic racism is part of every institution, the RCMP included."