(CNN) -- Police in Long Beach, California, are mourning a K9 officer that died apparently of heat-related causes in a department vehicle.
The dog, Ozzy, was found by its handler when both were off-duty about 3:40 p.m. on August 14, the Long Beach Police Department said in a statement.
"This unfortunate incident was not intentional," the statement reads. "Preliminarily, we believe this was an accident and we are taking all the necessary steps to avoid this happening in the future."
The department said its K9 vehicles have "fail/safe equipment that is meant to generate an alert," but it might not have been working, the statement said. The department statement said K9 handlers are checking their heat system controllers before every shift.
A veterinarian examined Ozzy. "The preliminary results determined the cause of death to be heat related," the police statement said.
The high temperature that day in Long Beach was 89 degrees, National Weather Service records show.
Police did not identify Ozzy's handler.
"Our department is mourning Ozzy's loss as we would with any of our employees. Our K9's are an indispensable part of our department, and we will continue to view them as our partners."
The Humane Society says it's never safe to leave pets locked in cars.
"It doesn't have to be that warm outside for a car to become dangerously hot inside," the organization's website says. "When it's 80 degrees Fahrenheit outside, the temperature inside your car can heat up to 99 degrees Fahrenheit within 10 minutes."