A six-year-old boy was sent to hospital after being shot by his four-year-old friend in an Indigenous community in Canada's Manitoba province, police said Thursday.

The two children were at a home on Peguis First Nation, about 185 kilometers (115 miles) north of Winnipeg, Monday night "when they gained access to a firearm," the Royal Canadian Mounted Police said in a statement.

"The four-year-old child discharged the firearm, which struck a six-year-old child," who was rushed to hospital for serious but non-life-threatening injuries, police said.

An adult male has been arrested and faces a charge of unlawful storage of firearms. Five guns and a crossbow were also seized.