The Galloway Township Police Department says K-9 Blaze collapsed after starting a training session indoors Wednesday.
Doctors at a veterinary hospital said the 6-year-old German shepherd's temperature indicated the death was not heat-related.
Blaze had been a patrol dog since 2007 and was the partner of Officer Scott Winneberger. Police say the dog was responsible for numerous criminal apprehensions and drug detections.
Blaze is the second Galloway Township police dog to die this year. K-9 Sabre died of cancer in April.
NOTE: A previous edition of this article stated that Blaze died of heat stroke. That report was based on incorrection information. We regret the error.