Warning after multiple children left alone in cars during NSW heatwave

Multiple children have been left alone in cars during Australia's brutal heatwave.

On Saturday afternoon, children aged two and nine were found alone in a car with the engine running, in a Griffith car park in NSW.

Later, another two children aged 11 and four were discovered by police alone in another car, this time in a supermarket car park. The car's windows were all up.

Police are investigating both cases and Family and Community Services have been alerted.

Police issued new warning ahead of record temperatures this week.

Murrumbidgee Police District Inspector Kim Traynor said: "By leaving your child in a car you are placing them at great risk of dehydration and heat stroke, or even abduction.

"We are urging the community to be mindful, particularly as the weather heats up.

"Leaving your children alone in a car so you can grab a few things from the shops is not only dangerous, it is irresponsible."

Pets should also not be left alone in cars, where temperatures can top 50C, even with windows open.

Multiple states are bracing for record temperatures this week.