A sweltering heatwave that has settled over western Canada for several days is believed to be a contributing factor in dozens of sudden-death calls received by police in the Vancouver area, authorities said on Tuesday.

Corporal Mike Kalanj of Burnaby Royal Canadian Mounted Police said the detachment responded to 25 sudden-death calls in a 24-hour period starting Monday. The deaths are still under investigation and many of the deceased were seniors, he said.

Temperatures in the Vancouver area reached just under 90 degrees Fahrenheit (32 degrees Celsius) on Monday, but the humidity made it feel close to 104 degrees Fahrenheit (40 degrees Celsius) in areas that aren’t near water, Environment Canada, the government department responsible for coordinating environmental policies and programmes, said.

The record-breaking heatwave could ease over parts of British Columbia, Yukon and the Northwest Territories by Wednesday, but any reprieve for the Prairie provinces is further off.

In Vancouver, the police department said it had redeployed dozens of officers and asked the public to call 911 only for emergencies because heat-related deaths had depleted front-line resources and delayed response times.

“Vancouver has never experienced heat like this, and sadly dozens of people are dying because of it,” Sergeant Steve Addison said in a news release. “Our officers are stretched thin, but we’re still doing everything we can to keep people safe.”

As of mid-afternoon on Tuesday, he said, police had responded to more than 65 sudden deaths since the heatwave began on Friday.

“The vast majority of these cases are related to the heat,” Addison said, adding that on a typical day, Vancouver police respond to between three and four sudden-death calls.

Ingrid Jarrett, CEO of the British Columbia Hotel Association, said residents in parts of the Lower Mainland, Victoria and the Okanagan region have been booking air-conditioned rooms so they can continue working and also get some sleep.

Environment Canada said the weather system shattered 103 heat records across British Columbia, Alberta, Yukon and Northwest Territories on Monday. Those records include a new Canadian high temperature of 118 degrees Fahrenheit) set in Lytton, British Columbia, smashing the previous record of 116 degrees Fahrenheit set in the same village a day earlier.