Children cool off standing under irrigation sprinklers at Warner Ranch Park in the Woodland Hills area of Los Angeles (File)

Authorities say extremely high temperatures in Los Angeles, California have contributed to the deaths of at least 25 people.

The region has been suffering under temperatures that have soared past 40 degrees Celsius for more than a week.

The heat wave has also caused a strain on the electricity supply in southern California as thousands of residents seek relief by turning on air conditioners. Utility crews have been working to restore power to tens of thousands of homes.

The U.S. National Weather Service says temperatures in the region are expected to fall to 10 degrees Celsius later Wednesday.

Some information for this report was provided by AFP, AP and Reuters.