Ottawa: Canadians deserve answers over the arrest of a prominent indigenous leader who alleges police beat him up after an incident involving an expired licence plate, Public Safety Minister Bill Blair said.

The Royal Canadian Mounted Police (RCMP) said officers used reasonable force after Chief Allan Adam of Athabasca Chipewyan First Nation resisted arrest outside a casino in the Alberta town of Fort McMurray in March. Adam released a photo of his swollen and bloodied face.

"We are deeply concerned by the incident that took place in Fort McMurray. People across the country deserve answers," Blair said on Twitter. Blair is in overall charge of law enforcement.

Canada has about 1.7 million people of indigenous descent, or just under 5 per cent of the overall population, many of whom live in communities hit by crime, ill-health and poverty. Complaints about police discrimination are widespread.