DEATH VALLEY NATIONAL PARK, Calif. — A tourist has died while visiting Death Valley National Park amid blazing summer heat.

The National Park Service says the visitor was reported to be non-responsive at 6 p.m. Tuesday and she died before emergency responders arrived at the location south of Badwater. Her name wasn’t released.

The cause of death is being investigated by Inyo County authorities, but the Park Service notes Death Valley has been having temperatures above 120 degrees.

It was the second death in three days in the Mojave Desert park, where two of the most common reasons for emergency responses are single-vehicle accidents and heat illnesses.

Summer visitors are urged to drink at least one gallon of water per day and watch for trouble signs including dizziness, nausea and headaches.