(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.

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