Hundreds of deaths have likely been caused by the heatwave moving across Canada and the US Northwest, authorities say.

The chief coroner of the Canadian province British Columbia said her office received reports of at least 486 “sudden and unexpected deaths” between Friday and Wednesday afternoon.

Lisa Lapointe said about 165 people normally would die in the province over a five-day period, adding that many of the most recent deaths could be heat related.

Health officials said more than 60 deaths in Oregon in the US have been tied to the heat, and at least 20 in Washington state.

Authorities have ordered residents to evacuate a village in British Columbia that smashed the country’s record for the hottest temperature three days in a row this week.

Mayor Jan Polderman of Lytton issued the evacuation order on Wednesday, saying on Twitter that the fire was threatening structures and the safety of residents of the community, which is 95 miles north east of Vancouver.

“All residents are advised to leave the community and go to a safe location,” Mr Polderman said.

In an interview with CBC News, the mayor said the situation was dire for the community of 250 people.

“The whole town is on fire,” he said. “It took, like, a whole 15 minutes from the first sign of smoke to, all of a sudden, there being fire everywhere.”

Erica Berg, a provincial fire information officer, said the evacuation order was issued about an hour after the blaze began but she did not know the size of it.

Highways north and south of the village were closed as firefighters also dealt with two other wildfires in the area.

Lytton’s temperature hovered around 39C (102F) on Wednesday. That was down from Tuesday, when the village recorded a new Canadian high of 49.6C (121.2F), breaking the previous highs of 47.9C (118.2F) it reached on Monday and 46.1C (115F) on Sunday.

The heatwave was caused by what meteorologists described as a dome of high pressure over the Northwest and worsened by human-caused climate change, which is making such extreme weather events more likely and more extreme.