Madrid - (AFP) - The heat wave that has hit Spain for 10 days has killed "more than 500 people," Spanish Prime Minister Pedro Sanchez said Wednesday during a trip to Aragon, the northern region of the country affected by the fires.

"During the heat wave, more than 500 people died due to high temperatures, according to statistics," he added, referring to estimates of the increase in death rates published by a public health institute.

"I ask the population to be very careful... the climate emergency is a fait accompli," he said.

Spain swept through a heat wave affecting most parts of Western Europe, which led to a rise in temperatures reaching 45 degrees Celsius in some areas last week, and caused the outbreak of dozens of forest fires.

Sanchez pointed to data from the Carlos III Institute of Health, which estimates the number of heat-related deaths based on the number of excess deaths when comparing numbers with rates recorded in previous years.

The institute has pointed out in recent days that its data are statistical estimates and are not an official death toll.