The fires in Spain this year have burned 158,000 hectares or 610 square miles, according to the European Union’s European Forest Fire Information System. That is an area roughly as big as metropolitan London.

Spain on Friday warned of "very high or extreme fire danger in most of the country," as firefighters there continue battling 14 blazes in temperatures up to 104 degrees Fahrenheit.

Firefighters and military units are struggling to contain wildfires in northwest and western Spain as a prolonged heatwave intensifies the crisis.